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Bibliography on: Symbiosis

The Electronic Scholarly Publishing Project: Providing world-wide, free access to classic scientific papers and other scholarly materials, since 1993.


ESP: PubMed Auto Bibliography 21 Sep 2021 at 01:50 Created: 


Symbiosis refers to an interaction between two or more different organisms living in close physical association, typically to the advantage of both. Symbiotic relationships were once thought to be exceptional situations. Recent studies, however, have shown that every multicellular eukaryote exists in a tight symbiotic relationship with billions of microbes. The associated microbial ecosystems are referred to as microbiome and the combination of a multicellular organism and its microbiota has been described as a holobiont. It seems "we are all lichens now."

Created with PubMed® Query: symbiosis NOT pmcbook NOT ispreviousversion

Citations The Papers (from PubMed®)


RevDate: 2021-09-20

Strohecker J, Golladay J, Paramo M, et al (2021)

Reactive Oxygen Species and the Stress Response in Octocorals.

Physiological and biochemical zoology : PBZ, 94(6):394-410.

AbstractReactive oxygen species (ROS) may damage cellular components but may also contribute to signaling that mitigates damage. In this context, the role of ROS in the stress response that leads to coral bleaching was investigated in three series of experiments with octocorals Sarcothelia sp. and Sympodium sp. Using video and fluorescent microscopy, the first experiments examined ROS and symbiont migration. Colonies mildly stressed with increased temperature and light showed increases in both ROS and numbers of migrating symbionts compared with stress-free controls. Symbionts migrating in the gastrovascular lumen may escape programmed cell death and provide a reservoir of healthy symbionts once conditions return to normal. In the second series of experiments, colonies were mildly stressed with elevated temperature and light. During stress, treated colonies were incubated in seawater enriched with two concentrations of bicarbonate (1 and 3 mmol/L), while controls were incubated in normal seawater. Bicarbonate enrichment provides additional carbon for photosynthesis and at some concentrations diminished the ROS emissions of stressed colonies of Sympodium sp. and Sarcothelia sp. In all experiments, the latter species tended to exhibit more ROS. Sympodium sp. contains Cladocopium sp. symbionts, which are less tolerant of stress, while Sarcothelia sp. contains the more resistant Durusdinium sp. Indeed, in direct comparisons, Sarcothelia sp. experienced higher levels of ROS under stress-free conditions and thus is conditioned to endure the stress associated with bleaching. Generally, ROS levels provide important insight into the cnidarian stress response and should be measured more often in studies of this response.

RevDate: 2021-09-20

Koko JH, Swift SOI, NA Hynson (2021)

Hawaiian Island endemic and indigenous plant species have higher mycorrhizal incidence than the global average.

American journal of botany [Epub ahead of print].

PREMISE: Prior efforts have shown that continents harbor a greater proportion of mycorrhizal hosts than on islands. However, in the Hawaiian Islands, estimates of the proportion of mycorrhizal plant species are higher than on continents (>90%), but there are few studies to support this claim. Concurrently, Hawaii's flora faces some of the greatest global risks of extinction, and significant efforts are aimed at restoring native vegetation. Arbuscular mycorrhizal (AM) fungi have been shown to improve plant restoration success, but little work has been done in Hawaii to understand the extent of mycorrhizal associations among native plant populations.

METHODS: We surveyed 35 native Hawaiian plant species in the wild, focusing on plant species that are reared for reintroduction. Roots from wild individuals were collected from 10 sites on Oahu to determine degree of mycorrhizal fungal colonization and how this varies across host populations.

RESULTS: Of the species surveyed, 97% had evidence of mycorrhizal colonization, including 25 endemic and nine indigenous species from 23 families. The mycorrhizal status of 22 of the species surveyed was unknown before this study. For four species, the degree of colonization by AM fungi differed among sites, and these differences corresponded with variations in precipitation and temperature.

CONCLUSIONS: The high incidence of mycorrhizal colonization provides evidence that island flora can actually harbor more mycorrhizal hosts than species on mainlands and that future reintroduction projects should consider the potentially important roles of AM fungi for success of these hosts in the wild.

RevDate: 2021-09-20

Torres N, Yu R, Martínez-Lüscher J, et al (2021)

Effects of Irrigation at Different Fractions of Crop Evapotranspiration on Water Productivity and Flavonoid Composition of Cabernet Sauvignon Grapevine.

Frontiers in plant science, 12:712622.

Climate change models predict lower precipitation and higher air temperatures that will negatively affect viticultural regions. Irrigation of vineyards will be crucial for mitigating abiotic stress during the growing season. However, the environmental impact of irrigation requires consideration for ensuring its sustainability in the future. We evaluated the standard irrigation practices on grapevine water use efficiency, berry flavonoid composition, vineyard water footprint, and arbuscular mycorrhizal fungi-grapevine symbiosis in two seasons with contrasting amounts of precipitation. The irrigation treatments consisted of weekly replacement of 25, 50, and 100% of crop evapotranspiration (ETc) during two growing seasons. Irrigation in grapevine vineyards mitigated the water scarcity when precipitation during the dormant season was not sufficient. The results provided field data supporting that despite the low rainfall recorded in one of the seasons, increasing the amount of irrigation was not advised, and replacing 50% ETc was sufficient. In this treatment, berry composition was improved with increased contents of total soluble solids, anthocyanins, and flavonols, and a stable flavonoid profile without an economic decrease in yield. In addition, with 50% ETc, the mycorrhizal symbiosis was not compromised and water resources were not highly impacted. Altogether, our results provide fundamental knowledge for viticulturists to design an appropriate irrigation schedule under the future warming scenarios with minimal environmental impact in semi-arid regions facing warming trends.

RevDate: 2021-09-20

Cuesta-Maté A, Renelies-Hamilton J, Kryger P, et al (2021)

Resistance and Vulnerability of Honeybee (Apis mellifera) Gut Bacteria to Commonly Used Pesticides.

Frontiers in microbiology, 12:717990.

Agricultural and apicultural practices expose honeybees to a range of pesticides that have the potential to negatively affect their physiology, neurobiology, and behavior. Accumulating evidence suggests that these effects extend to the honeybee gut microbiome, which serves important functions for honeybee health. Here we test the potential effects of the pesticides thiacloprid, acetamiprid, and oxalic acid on the gut microbiota of honeybees, first in direct in vitro inhibition assays and secondly in an in vivo caged bee experiment to test if exposure leads to gut microbiota community changes. We found that thiacloprid did not inhibit the honeybee core gut bacteria in vitro, nor did it affect overall community composition or richness in vivo. Acetamiprid did also not inhibit bacterial growth in vitro, but it did affect community structure within bees. The eight bacterial genera tested showed variable levels of susceptibility to oxalic acid in vitro. In vivo, treatment with this pesticide reduced amplicon sequence variant (ASV) richness and affected gut microbiome composition, with most marked impact on the common crop bacteria Lactobacillus kunkeei and the genus Bombella. We conducted network analyses which captured known associations between bacterial members and illustrated the sensitivity of the microbiome to environmental stressors. Our findings point to risks of honeybee exposure to oxalic acid, which has been deemed safe for use in treatment against Varroa mites in honeybee colonies, and we advocate for more extensive assessment of the long-term effects that it may have on honeybee health.

RevDate: 2021-09-20

Price DRG, Bartley K, Blake DP, et al (2021)

A Rickettsiella Endosymbiont Is a Potential Source of Essential B-Vitamins for the Poultry Red Mite, Dermanyssus gallinae.

Frontiers in microbiology, 12:695346.

Many obligate blood-sucking arthropods rely on symbiotic bacteria to provision essential B vitamins that are either missing or at sub-optimal levels in their nutritionally challenging blood diet. The poultry red mite Dermanyssus gallinae, an obligate blood-feeding ectoparasite, is a serious threat to the hen egg industry. Poultry red mite infestation has a major impact on hen health and welfare and causes a significant reduction in both egg quality and production. Thus far, the identity and biological role of nutrient provisioning bacterial mutualists from D. gallinae are little understood. Here, we demonstrate that an obligate intracellular bacterium of the Rickettsiella genus is detected in D. gallinae mites collected from 63 sites (from 15 countries) across Europe. In addition, we report the genome sequence of Rickettsiella from D. gallinae (Rickettsiella - D. gallinae endosymbiont; Rickettsiella DGE). Rickettsiella DGE has a circular 1.89Mbp genome that encodes 1,973 proteins. Phylogenetic analysis confirms the placement of Rickettsiella DGE within the Rickettsiella genus, related to a facultative endosymbiont from the pea aphid and Coxiella-like endosymbionts (CLEs) from blood feeding ticks. Analysis of the Rickettsiella DGE genome reveals that many protein-coding sequences are either pseudogenized or lost, but Rickettsiella DGE has retained several B vitamin biosynthesis pathways, suggesting the importance of these pathways in evolution of a nutritional symbiosis with D. gallinae. In silico metabolic pathway reconstruction revealed that Rickettsiella DGE is unable to synthesize protein amino acids and, therefore, amino acids are potentially provisioned by the host. In contrast, Rickettsiella DGE retains biosynthetic pathways for B vitamins: thiamine (vitamin B1) via the salvage pathway; riboflavin (vitamin B2) and pyridoxine (vitamin B6) and the cofactors: flavin adenine dinucleotide (FAD) and coenzyme A (CoA) that likely provision these nutrients to the host.

RevDate: 2021-09-20

Correia FP, LC Lourenço (2021)

Artificial intelligence application in diagnostic gastrointestinal endoscopy - Deus ex machina?.

World journal of gastroenterology, 27(32):5351-5361.

The close relationship of medicine with technology and the particular interest in this symbiosis in recent years has led to the development of several computed artificial intelligence (AI) systems aimed at various areas of medicine. A number of studies have demonstrated that those systems allow accurate diagnoses with histological precision, thus facilitating decision-making by clinicians in real time. In the field of gastroenterology, AI has been applied in the diagnosis of pathologies of the entire digestive tract and their attached glands, and are increasingly accepted for the detection of colorectal polyps and confirming their histological classification. Studies have shown high accuracy, sensitivity, and specificity in relation to expert endoscopists, and mainly in relation to those with less experience. Other applications that are increasingly studied and with very promising results are the investigation of dysplasia in patients with Barrett's esophagus and the endoscopic and histological assessment of colon inflammation in patients with ulcerative colitis. In some cases AI is thus better than or at least equal to human abilities. However, additional studies are needed to reinforce the existing data, and mainly to determine the applicability of this technology in other indications. This review summarizes the state of the art of AI in gastroenterological pathology.

RevDate: 2021-09-20

Abbaspour H, Pour FSN, MA Abdel-Wahhab (2021)

Arbuscular mycorrhizal symbiosis regulates the physiological responses, ion distribution and relevant gene expression to trigger salt stress tolerance in pistachio.

Physiology and molecular biology of plants : an international journal of functional plant biology, 27(8):1765-1778.

Mycorrhizal symbiosis is generally considered effective in ameliorating plant tolerance to abiotic stress by altering gene expression, and evaluation of genes involved in ion homeostasis and nutrient uptake. This study aimed to use arbuscular mycorrhizal fungus (AMF) to alleviate salinity stress and analyse relevant gene expression in pistachio plants under No/NaCl stress in greenhouse conditions. Arbuscular mycorrhizal symbiosis was used to study the physiological responses, ion distribution and relevant gene expression in pistachio plants under salinity stress. After four months of symbiosis, mycorrhizal root colonization showed a significant reduction in all tested parameters under salt stress treatment compared to non-saline treatment. Salinity affected the morphological traits, and decreased the nutrient content including N, P, Mg and Fe as well as K/Na and Ca/Na ratios, relative water content (RWC), membrane stability index (MSI), and increased the concentration of K, Ca and Na nutrient, glycine betaine, ROS and MDA. Inoculation of seedlings with AMF mitigated the negative effects of salinity on plant growth as indicated by increasing the root colonization, morphological traits, glycine betaine, RWC and MSI. Specifically, under salinity stress, shoot and root dry weight, P and Fe nutrient content, K/Na and Ca/Na ratio of AMF plants were increased by 53.2, 48.6, 71.6, 60.2, 87.5, and 80.1% respectively, in contrast to those of the NMF plants. The contents of Na, O2•- and MDA in AMF plants were significantly decreased by 66.8, 36.8, and 23.1%, respectively at 250 mM NaCl. Moreover, salinity markedly increased SOS1, CCX2 and SKOR genes expression and the inoculation with AMF modulated these genes expression; however, NRT2.4, PHO1 and PIP2.4 gene expressions were increased by salinity and AMF. It could be concluded that inoculation of AMF with Rhizophagus irregularis conferred a larger endurance towards soil salinity in pistachio plants and stimulate the nutrient uptake and ionic homeostasis maintenance, superior RWC and osmoprotection, toxic ion partitioning, maintaining membrane integrity and the ion-relevant genes expression.

RevDate: 2021-09-20

Das A, Begum K, Akhtar S, et al (2021)

Genome-wide detection and classification of terpene synthase genes in Aquilaria agallochum.

Physiology and molecular biology of plants : an international journal of functional plant biology, 27(8):1711-1729.

Agarwood, one of the precious woods in the globe, is produced by Aquilaria plant species during an upshot of wounding and infection. Produced as a defence response, the dark, fragrant resin gets secreted in the plant's duramen, which is impregnated with fragrant molecules with the due course. Agarwood has gained worldwide popularity due to its high aromatic oil, fragrance, and pharmaceutical value, which makes it highly solicited by numerous industries. Predominant chemical constituents of agarwood, sesquiterpenoids, and 2-(2-phenylethyl) chromones have been scrutinized to comprehend the scientific nature of the fragrant wood and develop novel products. However, the genes involved in the biosynthesis of these aromatic compounds are still not comprehensively studied in Aquilaria. In this study, publicly available genomic and transcriptomics data of Aquilaria agallochum were integrated to identify putative functional terpene synthase genes (TPSs). The in silico study enabled us to identify ninety-six TPSs, of which thirty-nine full-length genes were systematically classified into TPS-a, TPS-b, TPS-c, TPS-e, TPS-f, and TPS-g subfamilies based on their gene structure, conserve motif, and phylogenetic comparison with TPSs from other plant species. Analysis of the cis-regulatory elements present upstream of AaTPSs revealed their association with hormone, stress and light responses. In silico expression studies detected their up-regulation in stress induced tissue. This study provides a basic understanding of terpene synthase gene repertoire in Aquilaria agallochum and unlatches opportunities for the biochemical characterization and biotechnological exploration of these genes.

Supplementary Information: The online version contains supplementary material available at 10.1007/s12298-021-01040-z.

RevDate: 2021-09-19

Wang DL, Yang XQ, Shi WZ, et al (2021)

The selective anti-fungal metabolites from Irpex lacteus and applications in the chemical interaction of Gastrodia elata, Armillaria sp., and endophytes.

Fitoterapia pii:S0367-326X(21)00210-0 [Epub ahead of print].

The investigation of the metabolites from endophyte Irpex lacteus cultured in host "tian ma" (Gastrodia elata) revealed five new tremulane sesquiterpenes (1-5), and a new tetrahydrofuran derivative (6). Compound 1 was the first tremulane glucoside, and 6 possessed a rare tetrahydropyran-tetrahydrofuran scaffold. Main metabolite (2,3-dihydroxydodacane-4,7-dione, 14) from I. lacteus showed significant selectivity for antifungal activity against phytopathogen and endophytes associated with G. elata rather than against Armillaria sp. providing nutrition for the host G. elata. 14 accounted for 27.4% of isolated compounds from G. elata medium, and 69.3% by co-culturing with Armillaria sp. So the I. lacteus tended to promote the growth of Armillaria sp. in co-culture by producing 2,3-dihydroxydodacane-4,7-dione (14) to selective inhibit the phytopathogen and endophyte existed in host G. elata for the benefit of G. elata-Armillaria symbiosis. And the results were in accord with the real environment of G. elata depending on the nutrition of Armillaria. Some metabolites had anti-fungal activities against phytopathogens of G. elata with MICs ≤8 μg/mL.

RevDate: 2021-09-20
CmpDate: 2021-09-20

Russell AL, Fetters AM, James EI, et al (2021)

Pollinator effectiveness is affected by intraindividual behavioral variation.

Oecologia, 197(1):189-200.

Variation in pollinator quality is fundamental to the evolution of plant-pollinator mutualisms and such variation frequently results from differences in foraging behavior. Surprisingly, despite substantial intraindividual variation in pollinator foraging behavior, the consequences for pollen removal and deposition on flowers are largely unknown. We asked how two pollen foraging behaviors of a generalist pollinator (Bombus impatiens) affect removal and deposition of heterospecific and conspecific pollen, key aspects of pollinator quality, for multiple plant species. In addition, we examined how bee body size and pollen placement among body parts shaped pollen movement. We manipulated foraging behavior types using artificial flowers, which donated pollen that captive bees then deposited on three recipient plant species. While body size primarily affected donor pollen removal, foraging behavior primarily affected donor pollen deposition. How behavior affected donor pollen deposition depended on the plant species and the quantity of donor pollen on the bee's abdomen. Plant species with smaller stigmas received significantly less pollen and fewer bees successfully transferred pollen to them. For a single plant species, heterospecific pollen interfered with conspecific pollen deposition, such that more heterospecific pollen on the bee's abdomen resulted in less conspecific pollen deposition on the flower. Thus, intraindividual variation in foraging behavior and its interaction with the amount and placement of acquired pollen and with floral morphology can affect pollinator quality and may shape plant fitness via both conspecific and heterospecific pollen transfer.

RevDate: 2021-09-20
CmpDate: 2021-09-20

Camacho LF, L Avilés (2021)

Resource exchange and partner recognition mediate mutualistic interactions between prey and their would-be predators.

Biology letters, 17(8):20210316.

Animals may develop mutualistic associations with other species, whereby prey offer resources or services in exchange for protection from predators. Alternatively, prey may offer resources or services directly to their would-be predators in exchange for their lives. The latter may be the case of hemipterans that engage in mutualistic interactions with ants by offering a honeydew reward. We test the extent to which a honeydew offering versus partner recognition may play a role as proximate mechanisms deterring ants from predating upon their hemipteran partners. We showed that, when presented with a choice between a hemipteran partner and an alternative prey type, mutualist ants were less likely to attack and more likely to remain probing their hemipteran partners. This occurred even in the absence of an immediate sugary reward, suggesting either an evolved or learned partner recognition response. To a similar extent, however, ants were also less likely to attack the alternative prey type when laced with honey as a proxy for a honeydew reward. This was the case even after the honey had been depleted, suggesting an ability of ants to recognize new potential sources of sugars. Either possibility suggests a degree of innate or learned partner recognition.

RevDate: 2021-09-20
CmpDate: 2021-09-20

Soares GB, Domingues MV, EA Adriano (2021)

Morphological and molecular characterization of Udonella brasiliensis n. sp. (Monogenoidea), an epibiont on Caligus sp. parasite of Ariidae from the southeastern coast of Brazil.

Parasitology international, 83:102371.

The present study describes Udonella brasiliensis n. sp., an epibiont found on Caligus sp., a parasite the ariids Genidens barbus (Lacepède) and Aspistor luniscutis (Valenciennes), caught on the coast of the state of São Paulo, Brazil. Morphological and molecular analyses (partial 18S rDNA) were carried out. The morphological data showed that U. brasiliensis n. sp. can be distinguished from current valid species by its morphometric attributes (e.g., body, pharynx, ovary and testis), while the molecular information supports the proposal of a new species. The 18S rDNA phylogenetic analysis shows a close relationship between the new species and Udonella australis Carvajal & Sepulveda, in a subclade formed of species that parasitize South American fish. Finally, this study also discusses a scenario of initial irradiation for udonellids.

RevDate: 2021-09-20
CmpDate: 2021-09-20

Hou S, Wolinska KW, S Hacquard (2021)

Microbiota-root-shoot-environment axis and stress tolerance in plants.

Current opinion in plant biology, 62:102028.

Reminiscent to the microbiota-gut-brain axis described in animals, recent advances indicate that plants can take advantage of belowground microbial commensals to orchestrate aboveground stress responses. Integration of plant responses to microbial cues belowground and environmental cues aboveground emerges as a mechanism that promotes stress tolerance in plants. Using recent examples obtained from reductionist and community-level approaches, we discuss the extent to which perception of aboveground biotic and abiotic stresses can cascade along the shoot-root axis to sculpt root microbiota assembly and modulate the growth of root commensals that bolster aboveground stress tolerance. We propose that host modulation of microbiota-root-shoot circuits contributes to phenotypic plasticity and decision-making in plants, thereby promoting adaptation to rapidly changing environmental conditions.

RevDate: 2021-09-18

Kudo T, Aonuma H, E Hasegawa (2021)

A symbiotic aphid selfishly manipulates attending ants via dopamine in honeydew.

Scientific reports, 11(1):18569.

Symbiotic relationships are widespread in nature, but the mechanisms maintaining these relationships remain to be elucidated because symbiosis incurs a maintenance cost to each participant, which lowers its reproductive rate. In host-parasite relationships, parasites are known to manipulate the host's behavior selfishly, and there is an arms race between them. Selfish manipulations also occur in symbiosis, but the effects of selfish manipulations on symbiosis are not fully understood. Here, we show that an ant-associated aphid manipulates attending ants to receive stronger protection. Aphid honeydew regurgitated by ants contains dopamine (DA). The ants showed low aggressiveness before contact with the aphids, but it rose after contact. Administration of DA to the ants increased ant aggressiveness as the concentration increased, while an antagonist of DA inhibited this effect. The other 3 amines showed no effect on aggressiveness. A previous study showed that attending ants selfishly manipulate aphids by increasing the reproductive rate of green morph to obtain high-quality honeydew. These results suggest that mutual selfish manipulation benefits both participants and is likely to strengthen symbiosis. The selfishness of each participant may contribute to sustaining this symbiosis because their selfishness increases their long-term fitness.

RevDate: 2021-09-17

Nelson JM, Hauser DA, FW Li (2021)

The diversity and community structure of symbiotic cyanobacteria in hornworts inferred from long-read amplicon sequencing.

American journal of botany [Epub ahead of print].

PREMISE: Nitrogen-fixing endosymbioses with cyanobacteria have evolved independently in five very different plant lineages. Expanding knowledge of these symbioses promises to improve the understanding of symbiosis evolution and broaden the toolkit for agricultural engineering to reduce artificial fertilizer use. Here we focused on hornworts, a bryophyte lineage in which all members host cyanobacteria, and investigated factors shaping the diversity of their cyanobiont communities.

METHODS: We sampled hornworts and adjacent soils in upstate New York throughout the hornwort growing season. We included all three sympatric hornwort species in the area, allowing us to directly compare partner selectivity. To profile cyanobacteria communities, we established a metabarcoding protocol targeting rbcL-X with PacBio long reads.

RESULTS: The hornwort cyanobionts detected were phylogenetically diverse, including clades that do not contain other known plant symbionts. We found significant overlap between hornwort cyanobionts and soil cyanobacteria, a pattern not previously reported in other plant-cyanobacteria symbioses. Cyanobiont communities differed between host plants only centimeters apart, but we did not detect an effect of sampling time or host species on the cyanobacterial community structure.

CONCLUSIONS: This study expands the phylogenetic diversity of known symbiotic cyanobacteria. Our analyses suggest that hornwort cyanobionts have a tight connection to the soil background, and we found no evidence that time within growing season, host species, or distance at the scale of meters strongly govern cyanobacteria community assembly. This study provides a critical foundation for further study of the ecology, evolution, and interaction dynamics of plant-cyanobacteria symbiosis.

RevDate: 2021-09-17

Saboor A, Ali MA, Danish S, et al (2021)

Effect of arbuscular mycorrhizal fungi on the physiological functioning of maize under zinc-deficient soils.

Scientific reports, 11(1):18468.

Zinc (Zn) deficiency can severely inhibit plant growth, yield, and enzymatic activities. Zn plays a vital role in various enzymatic activities in plants. Arbuscular mycorrhizal fungi (AMF) play a crucial role in improving the plant's Zn nutrition and mitigating Zn stress effects on plants. The current study was conducted to compare the response of inoculated and non-inoculated maize (YH 1898) in the presence of different levels of zinc under greenhouse conditions under a Zn deficient condition. There were two mycorrhizal levels (i.e., M + with mycorrhizae, M- without mycorrhizae) and five Zn levels (i.e., 0, 1.5, 3, 6, and 12 mg kg-1), with three replicates following completely randomized design. At the vegetative stage (before tillering), biochemical, physiological, and agronomic attributes were measured. The results showed that maize plants previously inoculated with AMF had higher gaseous exchange traits, i.e., a higher stomatal conductance rate, favoring an increased photosynthetic rate. Improvement in antioxidant enzyme activity was also observed in inoculated compared to non-inoculated maize plants. Moreover, AMF inoculation also played a beneficial role in nutrients availability and its uptake by plants. Higher Zn12 (12 mg Zn kg-1 soil) treatment accumulated a higher Zn concentration in soil, root, and shoot in AMF-inoculated than in non-inoculated maize plants. These results are consistent with mycorrhizal symbiosis beneficial role for maize physiological functioning in Zn deficient soil conditions. Additionally, AMF inoculation mitigated the stress conditions and assisted nutrient uptake by maize.

RevDate: 2021-09-16

Kim DD, Wan L, Cao X, et al (2021)

Metagenomic insights into co-proliferation of Vibrio spp. and dinoflagellates Prorocentrum during a spring algal bloom in the coastal East China Sea.

Water research, 204:117625 pii:S0043-1354(21)00820-4 [Epub ahead of print].

Coastal harmful algal blooms (HABs), commonly termed 'red tides', have severe undesirable consequences to the marine ecosystems and local fishery and tourism industries. Increase in nitrogen and/or phosphorus loading is often regarded as the major culprits of increasing frequency and intensity of the coastal HAB; however, fundamental understanding is lacking as to the causes and mechanism of bloom formation despite decades of intensive investigation. In this study, we interrogated the prokaryotic microbiomes of surface water samples collected at two neighboring segments of East China Sea that contrast greatly in terms of the intensity and frequency of Prorocentrum-dominated HAB. Mantel tests identified significant correlations between the structural and functional composition of the microbiomes and the physicochemical state and the algal biomass density of the surface seawater, implying the possibility that prokaryotic microbiota may play key roles in the coastal HAB. A conspicuous feature of the microbiomes at the sites characterized with high trophic state index and eukaryotic algal cell counts was disproportionate proliferation of Vibrio spp., and their complete domination of the functional genes attributable to the dissimilatory nitrate reduction to ammonia (DNRA) pathway substantially enriched at these sites. The genes attributed to phosphorus uptake function were significantly enriched at these sites, presumably due to the Pi-deficiency induced by algal growth; however, the profiles of the phosphorus mineralization genes lacked consistency, barring any conclusive evidence with regard to contribution of prokaryotic microbiota to phosphorus bioavailability. The results of the co-occurrence network analysis performed with the core prokaryotic microbiome supported that the observed proliferation of Vibrio and HAB may be causally associated. The findings of this study suggest a previously unidentified association between Vibrio proliferation and the Prorocentrum-dominated HAB in the subtropical East China Sea, and opens a discussion regarding a theoretically unlikely, but still possible, involvement of Vibrio-mediated DNRA in Vibrio-Prorocentrum symbiosis. Further experimental substantiation of this supposed symbiotic mechanism may prove crucial in understanding the dynamics of explosive local algal growth in the region during spring algal blooms.

RevDate: 2021-09-16

Turney PD (2021)

Evolution of Autopoiesis and Multicellularity in the Game of Life.

Artificial life, 27(1):26-43.

Recently we introduced a model of symbiosis, Model-S, based on the evolution of seed patterns in Conway's Game of Life. In the model, the fitness of a seed pattern is measured by one-on-one competitions in the Immigration Game, a two-player variation of the Game of Life. Our previous article showed that Model-S can serve as a highly abstract, simplified model of biological life: (1) The initial seed pattern is analogous to a genome. (2) The changes as the game runs are analogous to the development of the phenome. (3) Tournament selection in Model-S is analogous to natural selection in biology. (4) The Immigration Game in Model-S is analogous to competition in biology. (5) The first three layers in Model-S are analogous to biological reproduction. (6) The fusion of seed patterns in Model-S is analogous to symbiosis. The current article takes this analogy two steps further: (7) Autopoietic structures in the Game of Life (still lifes, oscillators, and spaceships-collectively known as ashes) are analogous to cells in biology. (8) The seed patterns in the Game of Life give rise to multiple, diverse, cooperating autopoietic structures, analogous to multicellular biological life. We use the apgsearch software (Ash Pattern Generator Search), developed by Adam Goucher for the study of ashes, to analyze autopoiesis and multicellularity in Model-S. We find that the fitness of evolved seed patterns in Model-S is highly correlated with the diversity and quantity of multicellular autopoietic structures.

RevDate: 2021-09-16

Zhang J, Peng S, Li S, et al (2021)

Arachis hypogaea L. from Acid Soils of Nanyang (China) Is Frequently Associated with Bradyrhizobium guangdongense and Occasionally with Bradyrhizobium ottawaense or Three Bradyrhizobium Genospecies.

Microbial ecology [Epub ahead of print].

Henan Province is a major area of peanut production in China but the rhizobia nodulating the crop in this region have not been described. A collection of 217 strains of peanut rhizobia was obtained from six field sites across four soil types in Henan Province, North China, by using peanut as a trap host under glasshouse conditions. The 217 strains separated into 8 distinct types on PCR-RFLP analysis of their IGS sequences. Phylogenetic analysis of the 16S rRNA, recA, atpD, and glnII genes of 11 representative strains of the 8 IGS types identified Bradyrhizobium guangdongense, B. ottawaense and three novel Bradyrhizobium genospecies. Bradyrhizobium guangdongense was dominant, accounting for 75.0% of the total isolates across the field sites while B. ottawaense covered 5.1% and the three novel Bradyrhizobium genospecies 4.1 to 8.8% of the total. The symbiosis-related nodA and nifH gene sequences were not congruent with the core genes on phylogenetic analysis and separated into three groups, two of which were similar to sequences of Bradyrhizobium spp. isolated from peanut in south-east China and the third identical to that of B. yuanmingense isolated from Lespedeza cuneata in northern China. A canonical correlation analysis between the distribution of IGS genotypes and soil physicochemical characteristics and climatic factors indicated that the occurrence of IGS types/species was mainly associated with soil pH and available phosphorus.

RevDate: 2021-09-17

Altinli M, Schnettler E, M Sicard (2021)

Symbiotic Interactions Between Mosquitoes and Mosquito Viruses.

Frontiers in cellular and infection microbiology, 11:694020.

Mosquitoes not only transmit human and veterinary pathogens called arboviruses (arthropod-borne viruses) but also harbor mosquito-associated insect-specific viruses (mosquito viruses) that cannot infect vertebrates. In the past, studies investigating mosquito viruses mainly focused on highly pathogenic interactions that were easier to detect than those without visible symptoms. However, the recent advances in viral metagenomics have highlighted the abundance and diversity of viruses which do not generate mass mortality in host populations. Over the last decade, this has facilitated the rapid growth of virus discovery in mosquitoes. The circumstances around the discovery of mosquito viruses greatly affected how they have been studied so far. While earlier research mainly focused on the pathogenesis caused by DNA and some double-stranded RNA viruses during larval stages, more recently discovered single-stranded RNA mosquito viruses were heavily studied for their putative interference with arboviruses in female adults. Thus, many aspects of mosquito virus interactions with their hosts and host-microbiota are still unknown. In this context, considering mosquito viruses as endosymbionts can help to identify novel research areas, in particular in relation to their long-term interactions with their hosts (e.g. relationships during all life stages, the stability of the associations at evolutionary scales, transmission routes and virulence evolution) and the possible context-dependent range of interactions (i.e. beneficial to antagonistic). Here, we review the symbiotic interactions of mosquito viruses considering different aspects of their ecology, such as transmission, host specificity, host immune system and interactions with other symbionts within the host cellular arena. Finally, we highlight related research gaps in mosquito virus research.

RevDate: 2021-09-16

Wu N, Li Z, M Tang (2021)

Impact of salt and exogenous AM inoculation on indigenous microbial community structure in the rhizosphere of dioecious plant, Populus cathayana.

Scientific reports, 11(1):18403.

The sex-specific physical and biochemical responses in dioecious plants to abiotic stresses could result in gender imbalance, and how to ease the current situation by microorganisms is still unclear. Using native soil where poplars were grown, growth parameters, soil physicochemical properties in the rhizosphere soil of different sexes of Populus cathayana exposed to salt stress and exogenous arbuscular mycorrhizal (AM) inoculation were tested. Besides, the sex-specific microbial community structures in the rhizosphere soil of different sexes of Populus cathayana were compared under salt stress. To identify the sex-specific microbial community characteristics related to salinity and AM symbiosis, a combined qPCR and DGGE method was used to monitor microbial community diversity. Seedlings suffered severe pressure by salt stress, reflected in limited growth, biomass, and nutrient element accumulation, especially on females. Exogenous AM inoculation treatment alleviated these negative effects, especially under salt treatment of 75 mM. Compared with salt effect, exogenous AM inoculation treatment showed a greater effect on soil physical-chemical properties of both sexes. Based on DGGE results, salt stress negatively affected fungal richness but positively affected fungal Simpson diversity index, while exogenous AM inoculation treatment showed the opposite effect. Structural equation modeling (SEM) was performed to show the causal relationships between salt and exogenous AM inoculation treatments with biomass accumulation and microbial community: salt and exogenous AM inoculation treatment showed complicated effects on elementary concentrations, soil properties, which resulted in different relationship with biomass accumulation and microbial community. Salt stress had a negative effect on soil properties and microbial community structure in the rhizosphere soil of P. cathayana, whereas exogenous AM inoculation showed positive impacts on most of the soil physical-chemical properties and microbial community status.

RevDate: 2021-09-16

Worsley SF, Innocent TM, Holmes NA, et al (2021)

Competition-based screening helps to secure the evolutionary stability of a defensive microbiome.

BMC biology, 19(1):205.

BACKGROUND: The cuticular microbiomes of Acromyrmex leaf-cutting ants pose a conundrum in microbiome biology because they are freely colonisable, and yet the prevalence of the vertically transmitted bacteria Pseudonocardia, which contributes to the control of Escovopsis fungus garden disease, is never compromised by the secondary acquisition of other bacterial strains. Game theory suggests that competition-based screening can allow the selective recruitment of antibiotic-producing bacteria from the environment, by providing abundant resources to foment interference competition between bacterial species and by using Pseudonocardia to bias the outcome of competition in favour of antibiotic producers.

RESULTS: Here, we use RNA-stable isotope probing (RNA-SIP) to confirm that Acromyrmex ants can maintain a range of microbial symbionts on their cuticle by supplying public resources. We then used RNA sequencing, bioassays, and competition experiments to show that vertically transmitted Pseudonocardia strains produce antibacterials that differentially reduce the growth rates of other microbes, ultimately biassing the bacterial competition to allow the selective establishment of secondary antibiotic-producing strains while excluding non-antibiotic-producing strains that would parasitise the symbiosis.

CONCLUSIONS: Our findings are consistent with the hypothesis that competition-based screening is a plausible mechanism for maintaining the integrity of the co-adapted mutualism between the leaf-cutting ant farming symbiosis and its defensive microbiome. Our results have broader implications for explaining the stability of other complex symbioses involving horizontal acquisition.

RevDate: 2021-09-16
CmpDate: 2021-09-16

Santana SE, Kaliszewska ZA, Leiser-Miller LB, et al (2021)

Fruit odorants mediate co-specialization in a multispecies plant-animal mutualism.

Proceedings. Biological sciences, 288(1956):20210312.

Despite the widespread notion that animal-mediated seed dispersal led to the evolution of fruit traits that attract mutualistic frugivores, the dispersal syndrome hypothesis remains controversial, particularly for complex traits such as fruit scent. Here, we test this hypothesis in a community of mutualistic, ecologically important neotropical bats (Carollia spp.) and plants (Piper spp.) that communicate primarily via chemical signals. We found greater bat consumption is significantly associated with scent chemical diversity and presence of specific compounds, which fit multi-peak selective regime models in Piper. Through behavioural assays, we found Carollia prefer certain compounds, particularly 2-heptanol, which evolved as a unique feature of two Piper species highly consumed by these bats. Thus, we demonstrate that volatile compounds emitted by neotropical Piper fruits evolved in tandem with seed dispersal by scent-oriented Carollia bats. Specifically, fruit scent chemistry in some Piper species fits adaptive evolutionary scenarios consistent with a dispersal syndrome hypothesis. While other abiotic and biotic processes likely shaped the chemical composition of ripe fruit scent in Piper, our results provide some of the first evidence of the effect of bat frugivory on plant chemical diversity.

RevDate: 2021-09-17
CmpDate: 2021-09-17

Huang HJ, Ye YX, Ye ZX, et al (2021)

Chromosome-level genome assembly of the bean bug Riptortus pedestris.

Molecular ecology resources, 21(7):2423-2436.

The bean bug (Riptortus pedestris) causes great economic losses of soybeans by piercing and sucking pods and seeds. Although R. pedestris has become the focus of numerous studies associated with insect-microbe interactions, plant-insect interactions, and pesticide resistance, a lack of genomic resources has limited deeper insights. Here, we report the first R. pedestris genome at the chromosomal level using PacBio, Illumina, and Hi-C technologies. The assembled genome was 1.080 Gb in size with a contig N50 of 2.882 Mb. More than 96.3% of the total genome bases were successfully anchored to six unique chromosomes. Genome resequencing of male and female individuals and chromosomic staining demonstrated that the sex chromosome system of R. pedestris is XO, and the shortest chromosome is the X chromosome. In total, 19,026 protein-coding genes were predicted, 18,745 of which were validated as being expressed. Temporospatial expression of R. pedestris genes in six tissues and 37 development stages revealed 4,657 and 7,793 genes mainly expressed in gonads and egg periods, respectively. Evolutionary analysis demonstrated that R. pedestris and Oncopeltus fasciatus formed a sister group and split ∼80 million years ago (Mya). Additionally, a 5.04 Mb complete genome of symbiotic Serratia marcescens Rip1 was assembled, and the virulence factors that account for successful colonization in the host midgut were identified. The high-quality R. pedestris genome provides a valuable resource for further research, as well as for the pest management of bug pests.

RevDate: 2021-09-16
CmpDate: 2021-09-16

Gao H, Bai L, Jiang Y, et al (2021)

A natural symbiotic bacterium drives mosquito refractoriness to Plasmodium infection via secretion of an antimalarial lipase.

Nature microbiology, 6(6):806-817.

The stalling global progress in the fight against malaria prompts the urgent need to develop new intervention strategies. Whilst engineered symbiotic bacteria have been shown to confer mosquito resistance to parasite infection, a major challenge for field implementation is to address regulatory concerns. Here, we report the identification of a Plasmodium-blocking symbiotic bacterium, Serratia ureilytica Su_YN1, isolated from the midgut of wild Anopheles sinensis in China that inhibits malaria parasites via secretion of an antimalarial lipase. Analysis of Plasmodium vivax epidemic data indicates that local malaria cases in Tengchong (Yunnan province, China) are significantly lower than imported cases and importantly, that the local vector A. sinensis is more resistant to infection by P. vivax than A. sinensis from other regions. Analysis of the gut symbiotic bacteria of mosquitoes from Yunnan province led to the identification of S. ureilytica Su_YN1. This bacterium renders mosquitoes resistant to infection by the human parasite Plasmodium falciparum or the rodent parasite Plasmodium berghei via secretion of a lipase that selectively kills parasites at various stages. Importantly, Su_YN1 rapidly disseminates through mosquito populations by vertical and horizontal transmission, providing a potential tool for blocking malaria transmission in the field.

RevDate: 2021-09-15

Rosland NA, Ikhsan N, Min CC, et al (2021)

Influence of Symbiotic Probiont Strains on the Growth of Amphora and Chlorella and Its Potential Protections Against Vibrio spp. in Artemia.

Current microbiology [Epub ahead of print].

The emerging aquaculture industry is in need of non-antibiotic-based disease control approaches to minimize the risk of antibiotic-resistant bacteria. Bacterial infections mainly caused by Vibrio spp. have caused mass mortalities of fish especially during the larval stages. The objectives of this study were to verify the potential of symbiotic probiont strains, isolated from microalgae (Amphora, Chlorella, and Spirulina) for suppressing the growth of Vibrio spp. and at the same time ascertain their abilities to enhance microalgal biomass by mutualistic interactions through microalgae-bacteria symbiosis. In addition, in vivo studies on Artemia bioencapsulated with probiont strains (single strain and mix strains) and microalgae were evaluated. The selected potential probionts were identified as Lysinibacillus fusiformis strain A-1 (LFA-1), Bacillus sp. strain A-2 (BA-2), Lysinibacillus fusiformis strain Cl-3 (LFCl-3), and Bacillus pocheonensis strain S-2 (BPS-2) using 16s rRNA. The cell densities of Amphora culture supplemented with BA-2 and Chlorella culture supplemented with LFCl-3 were higher than those of the controls. Artemia bioencapsulated with mix strains (LFA-1 + BA-2 + LFCl-3 + BPS-2) and Amphora demonstrated the highest survival rate compared to the controls, after being challenged with V. harveyi (60 ± 4%) and V. parahaemolyticus (78 ± 2%). Our study postulated that BA-2 and LFCl-3 were found to be good promoting bacteria for microalgal growth and microalgae serve as a vector to transport probiotic into Artemia. Moreover, mixture of potential probionts is beneficial for Artemia supplementation in conferring protection to Artemia nauplii against pathogenic Vibrios.

RevDate: 2021-09-15

Jenkins BH, Maguire F, Leonard G, et al (2021)

Emergent RNA-RNA interactions can promote stability in a facultative phototrophic endosymbiosis.

Proceedings of the National Academy of Sciences of the United States of America, 118(38):.

Eukaryote-eukaryote endosymbiosis was responsible for the spread of chloroplast (plastid) organelles. Stability is required for the metabolic and genetic integration that drives the establishment of new organelles, yet the mechanisms that act to stabilize emergent endosymbioses-between two fundamentally selfish biological organisms-are unclear. Theory suggests that enforcement mechanisms, which punish misbehavior, may act to stabilize such interactions by resolving conflict. However, how such mechanisms can emerge in a facultative endosymbiosis has yet to be explored. Here, we propose that endosymbiont-host RNA-RNA interactions, arising from digestion of the endosymbiont population, can result in a cost to host growth for breakdown of the endosymbiosis. Using the model facultative endosymbiosis between Paramecium bursaria and Chlorella spp., we demonstrate that this mechanism is dependent on the host RNA-interference (RNAi) system. We reveal through small RNA (sRNA) sequencing that endosymbiont-derived messenger RNA (mRNA) released upon endosymbiont digestion can be processed by the host RNAi system into 23-nt sRNA. We predict multiple regions of shared sequence identity between endosymbiont and host mRNA, and demonstrate through delivery of synthetic endosymbiont sRNA that exposure to these regions can knock down expression of complementary host genes, resulting in a cost to host growth. This process of host gene knockdown in response to endosymbiont-derived RNA processing by host RNAi factors, which we term "RNAi collisions," represents a mechanism that can promote stability in a facultative eukaryote-eukaryote endosymbiosis. Specifically, by imposing a cost for breakdown of the endosymbiosis, endosymbiont-host RNA-RNA interactions may drive maintenance of the symbiosis across fluctuating ecological conditions.

RevDate: 2021-09-15
CmpDate: 2021-09-15

Wippel K, Tao K, Niu Y, et al (2021)

Host preference and invasiveness of commensal bacteria in the Lotus and Arabidopsis root microbiota.

Nature microbiology, 6(9):1150-1162.

Roots of different plant species are colonized by bacterial communities, that are distinct even when hosts share the same habitat. It remains unclear to what extent the host actively selects these communities and whether commensals are adapted to a specific plant species. To address this question, we assembled a sequence-indexed bacterial culture collection from roots and nodules of Lotus japonicus that contains representatives of most species previously identified using metagenomics. We analysed taxonomically paired synthetic communities from L. japonicus and Arabidopsis thaliana in a multi-species gnotobiotic system and detected signatures of host preference among commensal bacteria in a community context, but not in mono-associations. Sequential inoculation experiments revealed priority effects during root microbiota assembly, where established communities are resilient to invasion by latecomers, and that host preference of commensal bacteria confers a competitive advantage in their cognate host. Our findings show that host preference in commensal bacteria from diverse taxonomic groups is associated with their invasiveness into standing root-associated communities.

RevDate: 2021-09-15

Ledermann R, Schulte CCM, PS Poole (2021)

How Rhizobia Adapt to the Nodule Environment.

Journal of bacteriology, 203(12):e0053920.

Rhizobia are a phylogenetically diverse group of soil bacteria that engage in mutualistic interactions with legume plants. Although specifics of the symbioses differ between strains and plants, all symbioses ultimately result in the formation of specialized root nodule organs that host the nitrogen-fixing microsymbionts called bacteroids. Inside nodules, bacteroids encounter unique conditions that necessitate the global reprogramming of physiological processes and the rerouting of their metabolism. Decades of research have addressed these questions using genetics, omics approaches, and, more recently, computational modeling. Here, we discuss the common adaptations of rhizobia to the nodule environment that define the core principles of bacteroid functioning. All bacteroids are growth arrested and perform energy-intensive nitrogen fixation fueled by plant-provided C4-dicarboxylates at nanomolar oxygen levels. At the same time, bacteroids are subject to host control and sanctioning that ultimately determine their fitness and have fundamental importance for the evolution of a stable mutualistic relationship.

RevDate: 2021-09-14

Waterworth SC, Parker-Nance S, Kwan JC, et al (2021)

Comparative Genomics Provides Insight into the Function of Broad-Host Range Sponge Symbionts.

mBio [Epub ahead of print].

The fossil record indicates that the earliest evidence of extant marine sponges (phylum Porifera) existed during the Cambrian explosion and that their symbiosis with microbes may have begun in their extinct ancestors during the Precambrian period. Many symbionts have adapted to their sponge host, where they perform specific, specialized functions. There are also widely distributed bacterial taxa such as Poribacteria, SAUL, and Tethybacterales that are found in a broad range of invertebrate hosts. Here, we added 11 new genomes to the Tethybacterales order, identified a novel family, and show that functional potential differs between the three Tethybacterales families. We compare the Tethybacterales with the well-characterized Entoporibacteria and show that these symbionts appear to preferentially associate with low-microbial abundance (LMA) and high-microbial abundance (HMA) sponges, respectively. Within these sponges, we show that these symbionts likely perform distinct functions and may have undergone multiple association events, rather than a single association event followed by coevolution. IMPORTANCE Marine sponges often form symbiotic relationships with bacteria that fulfil a specific need within the sponge holobiont, and these symbionts are often conserved within a narrow range of related taxa. To date, there exist only three known bacterial taxa (Entoporibacteria, SAUL, and Tethybacterales) that are globally distributed and found in a broad range of sponge hosts, and little is known about the latter two. We show that the functional potential of broad-host range symbionts is conserved at a family level and that these symbionts have been acquired several times over evolutionary history. Finally, it appears that the Entoporibacteria are associated primarily with high-microbial abundance sponges, while the Tethybacterales associate with low-microbial abundance sponges.

RevDate: 2021-09-14

Qu Z, Zhang H, Wang Q, et al (2021)

Exploring the Symbiotic Mechanism of a Virus-Mediated Endophytic Fungus in Its Host by Dual Unique Molecular Identifier-RNA Sequencing.

mSystems [Epub ahead of print].

The symbiosis of endophytes and plants is universal in nature. However, how endophytes grow in plants is not entirely clear. Previously, we reported that a virus-infected fungal pathogen could grow in plants as an endophyte. In this study, we utilized Sclerotinia sclerotiorum strain DT-8, a virus-mediated endophyte, to investigate the mechanism of symbiosis with rapeseed by dual unique molecular identifier-RNA sequencing (dual-UMI RNA-seq). We found that the expressions of genes encoding S. sclerotiorum amylase/glucoamylase, glucose transporters, and rapeseed sugars will eventually be exported transporter 11 (SWEET11) were upregulated. It suggested that strain DT-8 might utilize plant starch as a nutrient. The defense systems of rapeseed were also activated, such as production of reactive oxygen species, phenylpropanoids, and brassinin, to control the growth of strain DT-8, while strain DT-8 counteracted host suppression by producing effector-like proteins, detoxification enzymes, and antioxidant components. Moreover, rapeseed also upregulated pectate lyase and pectinesterase genes to facilitate the colonization by strain DT-8. Our findings provide novel insights into the interaction of virus-mediated endophytes and their hosts that warrant further study. IMPORTANCE Although endophytes are widespread in nature, the interactions between endophytes and their hosts are still not fully understood. Members of a unique class of endophytes, the virus-mediated endophytic fungi, are continuously being discovered and have received wide attention. In this study, we investigated the interaction between a mycovirus-mediated endophytic fungus and its host rapeseed by using dual-UMI RNA-seq. According to the dual-UMI RNA-seq results, an aerial view of symbiotic mechanism under balanced regulation was suggested. This research expands our understanding of the symbiotic mechanisms of virus-fungus-plant interactions and could establish a foundation for the further development of practical application with virus-mediated hypovirulent fungi.

RevDate: 2021-09-14

Nagasawa M, T Kikusui (2021)

Neuroendocrine Mechanisms of Social Bonds and Separation Stress in Rodents, Dogs, and Other Species.

Current topics in behavioral neurosciences [Epub ahead of print].

Mammalian species form unique bonds between mothers and infants. Maternal care, including suckling, is necessary for infant survival, and the mother and, sometimes, the father require a lot of effort in nurturing infants. An infant's probability of survival depends on the extent of the investment of care by the mother. In parallel, mothers must identify their offspring and invest only in those who possess their genes to achieve evolutionary benefits. Therefore, they need to recognize their offspring and show a strong preference for them. For this reason, bond formation between mothers and infants is important. The mother monitors her offspring's physical condition and stays close to them. The offspring also form strong bonds with their mothers. Therefore, a separation between the mother and infant causes severe stress for both parties. Although it was initially thought that such bonds between mother and infant are limited to the same species, we have also observed a similar phenomenon in the human-dog relationship. In this article, we discuss the neuroendocrine mechanisms that underlie bond formation and separation based on findings of neurobiological research in mice and the relationship between humans and dogs.

RevDate: 2021-09-14
CmpDate: 2021-09-14

Bordon Y (2021)

Inner viruses ignite immunity to commensals.

Nature reviews. Immunology, 21(8):471.

RevDate: 2021-09-13

Aroney STN, Poole PS, C Sánchez-Cañizares (2021)

Rhizobial Chemotaxis and Motility Systems at Work in the Soil.

Frontiers in plant science, 12:725338.

Bacteria navigate their way often as individual cells through their chemical and biological environment in aqueous medium or across solid surfaces. They swim when starved or in response to physical and chemical stimuli. Flagella-driven chemotaxis in bacteria has emerged as a paradigm for both signal transduction and cellular decision-making. By altering motility, bacteria swim toward nutrient-rich environments, movement modulated by their chemotaxis systems with the addition of pili for surface movement. The numbers and types of chemoreceptors reflect the bacterial niche and lifestyle, with those adapted to complex environments having diverse metabolic capabilities, encoding far more chemoreceptors in their genomes. The Alpha-proteobacteria typify the latter case, with soil bacteria such as rhizobia, endosymbionts of legume plants, where motility and chemotaxis are essential for competitive symbiosis initiation, among other processes. This review describes the current knowledge of motility and chemotaxis in six model soil bacteria: Sinorhizobium meliloti, Agrobacterium fabacearum, Rhizobium leguminosarum, Azorhizobium caulinodans, Azospirillum brasilense, and Bradyrhizobium diazoefficiens. Although motility and chemotaxis systems have a conserved core, rhizobia possess several modifications that optimize their movements in soil and root surface environments. The soil provides a unique challenge for microbial mobility, since water pathways through particles are not always continuous, especially in drier conditions. The effectiveness of symbiont inoculants in a field context relies on their mobility and dispersal through the soil, often assisted by water percolation or macroorganism movement or networks. Thus, this review summarizes the factors that make it essential to consider and test rhizobial motility and chemotaxis for any potential inoculant.

RevDate: 2021-09-13

Goddard ML, Belval L, Martin IR, et al (2021)

Arbuscular Mycorrhizal Symbiosis Triggers Major Changes in Primary Metabolism Together With Modification of Defense Responses and Signaling in Both Roots and Leaves of Vitis vinifera.

Frontiers in plant science, 12:721614.

Grapevine (Vitis vinifera L.) is one of the most important crops worldwide but is subjected to multiple biotic and abiotic stresses, especially related to climate change. In this context, the grapevine culture could take advantage of symbiosis through association with arbuscular mycorrhizal fungi (AMF), which are able to establish symbiosis with most terrestrial plants. Indeed, it is well established that mycorrhization improves grapevine nutrition and resistance to stresses, especially water stress and resistance to root pathogens. Thus, it appears essential to understand the effect of mycorrhization on grapevine metabolism and defense responses. In this study, we combined a non-targeted metabolomic approach and a targeted transcriptomic study to analyze changes induced in both the roots and leaves of V. vinifera cv. Gewurztraminer by colonization with Rhizophagus irregularis (Ri). We showed that colonization of grapevine with AMF triggers major reprogramming of primary metabolism in the roots, especially sugar and fatty acid metabolism. On the other hand, mycorrhizal roots had decreased contents of most sugars and sugar acids. A significant increase in several fatty acids (C16:1, linoleic and linolenic acids and the C20 arachidonic and eicosapentaenoic acids) was also detected. However, a downregulation of the JA biosynthesis pathway was evidenced. We also found strong induction of the expression of PR proteins from the proteinase inhibitor (PR6) and subtilase (PR7) families in roots, suggesting that these proteins are involved in the mycorrhiza development but could also confer higher resistance to root pathogens. Metabolic changes induced by mycorrhization were less marked in leaves but involved higher levels of linoleic and linolenic acids and decreased sucrose, quinic, and shikimic acid contents. In addition, Ri colonization resulted in enhanced JA and SA levels in leaves. Overall, this study provides a detailed picture of metabolic changes induced by AMF colonization in a woody, economically important species. Moreover, stimulation of fatty acid biosynthesis and PR protein expression in roots and enhanced defense hormone contents in leaves establish first insight in favor of better resistance of grapevine to various pathogens provided by AMF colonization.

RevDate: 2021-09-13

Nesbitt H, Burke C, M Haghi (2021)

Manipulation of the Upper Respiratory Microbiota to Reduce Incidence and Severity of Upper Respiratory Viral Infections: A Literature Review.

Frontiers in microbiology, 12:713703.

There is a high incidence of upper respiratory viral infections in the human population, with infection severity being unique to each individual. Upper respiratory viruses have been associated previously with secondary bacterial infection, however, several cross-sectional studies analyzed in the literature indicate that an inverse relationship can also occur. Pathobiont abundance and/or bacterial dysbiosis can impair epithelial integrity and predispose an individual to viral infection. In this review we describe common commensal microorganisms that have the capacity to reduce the abundance of pathobionts and maintain bacterial symbiosis in the upper respiratory tract and discuss the potential and limitations of localized probiotic formulations of commensal bacteria to reduce the incidence and severity of viral infections.

RevDate: 2021-09-13

He X, Xie H, Gao D, et al (2021)

Biochar and Intercropping With Potato-Onion Enhanced the Growth and Yield Advantages of Tomato by Regulating the Soil Properties, Nutrient Uptake, and Soil Microbial Community.

Frontiers in microbiology, 12:695447.

The application of biochar stimulates the activities of microorganisms that affect soil quality and plant growth. However, studies on the impacts of biochar mainly focus on a monoculture, its effects on interspecific interactions are rarely reported. Here, we investigated the impacts of biochar on tomato/potato-onion intercropped (TO) in a pot experiment. Tomato monoculture (T) and TO were treated with no, 0.3, 0.6, and 1.2% biochar concentrations in a pot experiment. Microbial communities from tomato rhizosphere soil were analyzed by quantitative PCR and Illumina MiSeq. The results showed that compared with the tomato monoculture, 0.6%TO and 1.2%TO significantly increased tomato yield in 2018. TO and 1.2%TO significantly increased plant height and dry weight in 2018 and 2019. Biochar treatments increased soil pH, decreased NO 3 - -N and bulk density, and increased the absorption of N, P, and K by tomato. Bacterial and fungal abundances increased with an increase in biochar concentration, while Bacillus spp. and Pseudomonas spp. abundances showed an "increase-decrease-increase" trend. Biochar had a little effect on bacterial diversities but significantly lowered fungal diversities. TO, 0.6%TO, and 1.2%TO increased the potentially beneficial organisms (e.g., Pseudeurotium and Solirubrobacter) and lowered the potentially pathogenic organisms (e.g., Kribbella and Ilyonectria). Different concentrations of biochar affected the bacterial and fungal community structures. Redundancy analysis indicated that the bacterial community was strongly correlated with soil pH, NO 3 - -N, and EC, while the fungal community was closely related to soil NO 3 - -N and moisture. The network analysis showed that biochar and intercropping affected the symbiosis pattern of the microorganisms and increased the proportion of positive interactions and nitrifying microorganisms (Nitrospirae) in the microbial community. Overall, our results indicated that monoculture and intercropping with biochar improved soil physicochemical states and plant nutrient absorption, and regulated soil microbial communities, these were the main factors to promote tomato growth and increase tomato productivity.

RevDate: 2021-09-13

Kise H, Obuchi M, JD Reimer (2021)

A new Antipathozoanthus species (Cnidaria, Hexacorallia, Zoantharia) from the northwest Pacific Ocean.

ZooKeys, 1040:49-64 pii:62309.

A new species of zoantharian within the genus Antipathozoanthus is described based on specimens collected from the coast of mainland Japan, northwest Pacific Ocean. Antipathozoanthustubus sp. nov. is characterized by its substrate (epibiotic on polychaete tube) and habitat (exposed rock). As well, the results of molecular phylogenetic analyses using concatenated multiple genetic markers also support the distinction between A.tubus sp. nov. and its congenerics. Antipathozoanthustubus sp. nov. is the first species of Antipathozoanthus species reported to be epibiotic on polychaete tubes, and is the second species in the genus that is not associated with antipatharians.

RevDate: 2021-09-13

Chen X, Hu A, Zou Q, et al (2021)

The Mesorhizobium huakuii transcriptional regulator AbiEi plays a critical role in nodulation and is important for bacterial stress response.

BMC microbiology, 21(1):245.

BACKGROUND: Bacterial abortive infection (Abi) systems are type IV toxin-antitoxin (TA) system, which could elicit programmed cell death and constitute a native survival strategy of pathogenic bacteria under various stress conditions. However, no rhizobial AbiE family TA system has been reported so far. Here, a M. huakuii AbiE TA system was identified and characterized.

RESULTS: A mutation in M. huakuii abiEi gene, encoding an adjacent GntR-type transcriptional regulator, was generated by homologous recombination. The abiEi mutant strain grew less well in rich TY medium, and displayed increased antioxidative capacity and enhanced gentamicin resistance, indicating the abiEi operon was negatively regulated by the antitoxin AbiEi in response to the oxidative stress and a particular antibiotic. The mRNA expression of abiEi gene was significantly up-regulated during Astragalus sinicus nodule development. The abiEi mutant was severely impaired in its competitive ability in rhizosphere colonization, and was defective in nodulation with 97% reduction in nitrogen-fixing capacity. The mutant infected nodule cells contained vacuolation and a small number of abnormal bacteroids with senescence character. RNA-seq experiment revealed it had 5 up-regulated and 111 down-regulated genes relative to wild type. Of these down-regulated genes, 21 are related to symbiosis nitrogen fixation and nitrogen mechanism, 16 are involved in the electron transport chain and antioxidant responses, and 12 belong to type VI secretion system (T6SS).

CONCLUSIONS: M. huakuii AbiEi behaves as a key transcriptional regulator mediating root nodule symbiosis.

RevDate: 2021-09-12

Rangel LI, Hamilton O, de Jonge R, et al (2021)

Fungal social influencers: secondary metabolites as a platform for shaping the plant-associated community.

The Plant journal : for cell and molecular biology [Epub ahead of print].

Fungal secondary metabolites (FSMs) are capable of manipulating plant community dynamics by inhibiting or facilitating the establishment of co-habitating organisms. Although production of FSMs is not crucial for survival of the producer, their absence can indirectly impair growth and/or niche competition of these fungi on the plant. Presence of FSMs with no obvious consequence on the fitness of the producer leaves questions regarding ecological impact. This review investigates how fungi employ FSMs as a platform to mediate fungal-fungal, fungal-bacterial, and fungal-animal interactions associated with the plant community. We discuss how the biological function of FSMs may indirectly benefit the producer by altering the dynamics of surrounding organisms. We introduce several instances where FSMs influence antagonistic- or alliance-driven interactions. Part of our aim is to decipher the meaning of the FSM 'language' since it is widely noted to impact the surrounding community. Here, we highlight the contribution of FSMs to plant-associated interaction networks that affect the host either broadly or in ways that may have previously been unclear.

RevDate: 2021-09-12

Pereira AM, A Clemente (2021)

Dogs' microbiome from tip to toe.

Topics in companion animal medicine pii:S1938-9736(21)00077-5 [Epub ahead of print].

Microbiota and microbiome, which refers, respectively, to the microorganisms and conjoint of microorganisms and genes are known to live in symbiosis with hosts, being implicated in health and disease. The advancements and cost reduction associated with high-throughput sequencing techniques have allowed expanding the knowledge of microbial communities in several species, including dogs. Throughout their body, dogs harbor distinct microbial communities according to the location (e.g., skin, ear canal, conjunctiva, respiratory tract, genitourinary tract, gut), which have been a target of study mostly in the last couple of years. Although there might be a core microbiota for different body sites, shared by dogs, it is likely influenced by intrinsic factors such as age, breed, and sex, but also by extrinsic factors such as the environment (e.g., lifestyle, urban vs rural), and diet. It starts to become clear that some medical conditions are mediated by alterations in microbiota namely dysbiosis. Moreover, understanding microbial colonization and function can be used to prevent medical conditions, for instance, modulation of gut microbiota of puppies is more effective to ensure a healthy gut than interventions in adults. This paper gathers current knowledge of dogs' microbial communities, exploring their function, implications in the development of diseases, and potential interactions among communities while providing hints for further research.

RevDate: 2021-09-13
CmpDate: 2021-09-13

Ióca LP, Dai Y, Kunakom S, et al (2021)

A Family of Nonribosomal Peptides Modulate Collective Behavior in Pseudovibrio Bacteria Isolated from Marine Sponges*.

Angewandte Chemie (International ed. in English), 60(29):15891-15898.

Although swarming motility and biofilms are opposed collective behaviors, both contribute to bacterial survival and host colonization. Pseudovibrio bacteria have attracted attention because they are part of the microbiome of healthy marine sponges. Two-thirds of Pseudovibrio genomes contain a member of a nonribosomal peptide synthetase-polyketide synthase gene cluster family, which is also found sporadically in Pseudomonas pathogens of insects and plants. After developing reverse genetics for Pseudovibrio, we isolated heptapeptides with an ureido linkage and related nonadepsipeptides we termed pseudovibriamides A and B, respectively. A combination of genetics and imaging mass spectrometry experiments showed heptapetides were excreted, promoting motility and reducing biofilm formation. In contrast to lipopeptides widely known to affect motility/biofilms, pseudovibriamides are not surfactants. Our results expand current knowledge on metabolites mediating bacterial collective behavior.

RevDate: 2021-09-13
CmpDate: 2021-09-13

Maeda T, Takahashi S, Yoshida T, et al (2021)

Chloroplast acquisition without the gene transfer in kleptoplastic sea slugs, Plakobranchus ocellatus.

eLife, 10:.

Some sea slugs sequester chloroplasts from algal food in their intestinal cells and photosynthesize for months. This phenomenon, kleptoplasty, poses a question of how the chloroplast retains its activity without the algal nucleus. There have been debates on the horizontal transfer of algal genes to the animal nucleus. To settle the arguments, this study reported the genome of a kleptoplastic sea slug, Plakobranchus ocellatus, and found no evidence of photosynthetic genes encoded on the nucleus. Nevertheless, it was confirmed that light illumination prolongs the life of mollusk under starvation. These data presented a paradigm that a complex adaptive trait, as typified by photosynthesis, can be transferred between eukaryotic kingdoms by a unique organelle transmission without nuclear gene transfer. Our phylogenomic analysis showed that genes for proteolysis and immunity undergo gene expansion and are up-regulated in chloroplast-enriched tissue, suggesting that these molluskan genes are involved in the phenotype acquisition without horizontal gene transfer.

RevDate: 2021-09-13
CmpDate: 2021-09-13

Lee J, Davidson TM, ME Torchin (2021)

Variable host responses mediate host preference in marine flatworm-snail symbioses.

PloS one, 16(3):e0247551.

Host preference of symbionts evolves from fitness trade-offs. However, it is often unclear how interspecific variations in host response traits influence this evolutionary process. Using the association between the polyclad flatworm Paraprostatum echinolittorinae and its intertidal snail hosts on the Pacific Coast of Panama, we assessed how a symbiont's host preference is associated with varying host defenses and post-infestation performances. We first characterized the prevalence and intensity of worm infestation in five snail hosts (Tegula pellisserpentis, Nerita scabricosta, N. funiculata, Planaxis planicostatus, and Cerithium stercusmuscarum). We then used manipulative experiments to test flatworm's host choice, hosts' behavioral rejection of flatworms, and hosts' growth and survival following the infestation. In the field, flatworms were orders of magnitude more prevalent and dense in T. pellisserpentis, N. scabricosta, N. funiculata than P. planicostatus and C. stercusmuscarum, although the three former hosts were not necessarily more abundant. The results from our laboratory host selection trials mirrored these patterns; flatworms were 3 to 14 times more likely to choose T. pellisserpentis, N. scabricosta, N. funiculata over P. planicostatus and C. stercusmuscarum. The less preferred hosts frequently rejected flatworms via mantle contractions and foot withdrawals, which reduced the infestation rate by 39%-67%. These behaviors were less frequent or absent in the preferred hosts. Flatworm infestation variably influenced host performances in the field, negligibly affecting the growth and survival of T. pellisserpentis and N. funiculata but reducing the growth of P. planicostatus. Flatworms thus preferred less defended hosts that can also support higher worm densities without being harmed. Stable isotope analysis further revealed that flatworms are unlikely to feed on snail tissues and may live as a commensal in their preferred hosts. Our study demonstrates that host response traits can modulate a symbiont's host choice and calls for more explicit considerations of host response variability in host preference research.

RevDate: 2021-09-13
CmpDate: 2021-09-13

Khalmuratova I, Choi DH, Yoon HJ, et al (2021)

Diversity and Plant Growth Promotion of Fungal Endophytes in Five Halophytes from the Buan Salt Marsh.

Journal of microbiology and biotechnology, 31(3):408-418.

The diversity and plant growth-promoting ability of fungal endophytes that are associated with five halophytic plant species (Phragmites australis, Suaeda australis, Limonium tetragonum, Suaeda glauca Bunge, and Suaeda maritima) growing in the Buan salt marsh on the west coast of South Korea have been explored. About 188 fungal strains were isolated from these plant samples' roots and were then studied with the use of the internal transcribed spacer (ITS) region (ITS1-5.8S-ITS2). The endophytic fungal strains belonged to 33 genera. Alternaria (18%) and Fusarium (12.8%), of the classes Dothideomycetes and Sordariomycetes, were most rampant in the coastal salt marsh plants. There was a higher diversity in fungal endophytes that are isolated from S. glauca Bunge than in isolates from other coastal salt marsh plants. Plant growth-promoting experiments with the use of Waito-C rice seedlings show that some of the fungal strains could encourage a more efficient growth than others. Furthermore, gibberellins (GAs) GA1, GA3, and GA9 were seen in the Sa-1-4-3 isolate (Acrostalagmus luteoalbus) culture filtrate with a gas chromatography/mass spectrometry.

RevDate: 2021-09-13
CmpDate: 2021-09-13

Na H, Jo SW, Do JM, et al (2021)

Production of Algal Biomass and High-Value Compounds Mediated by Interaction of Microalgal Oocystis sp. KNUA044 and Bacterium Sphingomonas KNU100.

Journal of microbiology and biotechnology, 31(3):387-397.

There is growing interest in the production of microalgae-based, high-value by-products as an emerging green biotechnology. However, a cultivation platform for Oocystis sp. has yet to be established. We therefore examined the effects of bacterial culture additions on the growth and production of valuable compounds of the microalgal strain Oocystis sp. KNUA044, isolated from a locally adapted region in Korea. The strain grew only in the presence of a clear supernatant of Sphingomonas sp. KNU100 culture solution and generated 28.57 mg/l/d of biomass productivity. Protein content (43.9 wt%) was approximately two-fold higher than carbohydrate content (29.4 wt%) and lipid content (13.9 wt%). Oocystis sp. KNUA044 produced the monosaccharide fucose (33 μg/mg and 0.94 mg/l/d), reported here for the first time. Fatty acid profiling showed high accumulation (over 60%) of polyunsaturated fatty acids (PUFAs) compared to saturated (29.4%) and monounsaturated fatty acids (9.9%) under the same culture conditions. Of these PUFAs, the algal strain produced the highest concentration of linolenic acid (C18:3 ω3; 40.2%) in the omega-3 family and generated eicosapentaenoic acid (C20:5 ω3; 6.0%), also known as EPA. Based on these results, we suggest that the application of Sphingomonas sp. KNU100 for strain-dependent cultivation of Oocystis sp. KNUA044 holds future promise as a bioprocess capable of increasing algal biomass and high-value bioactive by-products, including fucose and PUFAs such as linolenic acid and EPA.

RevDate: 2021-09-11

Xi L, Shen Y, Zhao X, et al (2021)

Effects of arbuscular mycorrhizal fungi on frond antimony enrichment, morphology, and proteomics in Pteris cretica var. nervosa during antimony phytoremediation.

The Science of the total environment, 804:149904 pii:S0048-9697(21)04979-2 [Epub ahead of print].

Pteris cretica var. nervosa is a dominant fern species found in antimony (Sb) mining areas, capable of forming symbiosis with arbuscular mycorrhizal fungi (AMF), especially with those members of the Glomus genus. Despite this fern's relevance and the potential contribution of mycorrhizal symbiosis to phytoremediation, the AMF's impact on P. var. nervosa phytoremediation of Sb remains unknown. Here, we exposed P. var. nervosa to different concentrations of Sb for 6 months. Our results showed that Sb reduced shoot biomass, enlarged the root/shoot ratio, and disrupted the fronds' intracellular structure. AMF inoculation, however, was able to moderate these phenotypic changes and increased the accumulation level of Sb in plants. From a proteomics analysis of this plant's fronds, a total of 283 proteins were identified. Notably, those proteins with catalytic function, carbon fixing and ATP metabolic function were highly enriched. K-means clustering demonstrated protein-changing patterns involved in multiple metabolic pathways during exposure to Sb. Further, these patterns can be moderated by AMF inoculation. Pearson correlations were used to assess the plant biomarkers-soil Sb relationships; This revealed a strong correlation between ribosome alteration and the root/shoot ratio when inoculated with AMF, and a positive correlation between photosynthesis proteins and chlorophyll (SPAD value). Our results indicate AMF could moderate the fronds impairment by maintaining the sufficient protein levels for ribosomal functioning, photosynthesis activity and to counter ROS production. We demonstrate the effective use of AMF associated with P. cretica var. nervosa for Sb phytoremediation and the potential of applying proteomics to better understand the mechanism behind this symbiotic plant physiological response.

RevDate: 2021-09-11

van de Guchte M, Mondot S, J Doré (2021)

Dynamic properties of the intestinal ecosystem call for combination therapies, targeting inflammation and microbiota, in ulcerative colitis.

Gastroenterology pii:S0016-5085(21)03482-X [Epub ahead of print].

BACKGROUND AND AIMS: Intestinal microbiota - host interactions play a major role in health and disease. This has been documented at the microbiota level ("dysbiosis" in chronic immune-mediated diseases) and through the study of specific bacteria - host interactions, but rarely at the level of intestinal ecosystem dynamics. Yet, understanding the behavior of this ecosystem may be key to the successful treatment of disease. We recently postulated that health and disease represent alternative stable states of the intestinal ecosystem (different configurations that can exist under identical external conditions), which would demand for adapted strategies in disease treatment. Here, we examine if alternative stable states indeed exist in this ecosystem, and if they could affect remission from ulcerative colitis (UC).

METHODS: We analyzed data from a study on pediatric UC. The data reflect current treatment practice following the recruitment of new-onset, treatment-naïve, patients. Patients received personalized anti-inflammatory treatments over a period of one year. Stool samples at 0, 4, 12 and 52 weeks allowed an estimation of microbiota status (through 16S rRNA gene sequencing) and host inflammatory status (through the measurement of fecal calprotectin levels).

RESULTS: We identify four microbiota states and four host states. Longitudinal data show that the improvement of inflammatory status is accompanied by an improvement of microbiota status. However, they also provide strong indications that both improvements are retarded or blocked by alternative states barriers.

CONCLUSIONS: Our observations strongly suggest that inflammation suppression should be combined with microbiota management where possible to improve the efficacy of UC treatment.

RevDate: 2021-09-10

Xu S, Chen J, Qin M, et al (2021)

Geography-dependent symbiont communities in two oligophagous aphid species.

FEMS microbiology ecology pii:6368335 [Epub ahead of print].

Aphids and their diverse symbionts have become a good model to study bacteria-arthropod symbiosis. The feeding habits of aphids are usually influenced by a variety of symbionts. Most studies on symbiont diversity have focused on polyphagous aphids, while symbiont community patterns for oligophagous aphids remain unclear. Here, we surveyed the bacterial communities in natural populations of two oligophagous aphids, Melanaphis sacchari and Neophyllaphis podocarpi, in natural populations. Seven common symbionts were detected, among which Buchnera aphidicola and Wolbachia were the most prevalent. In addition, an uncommon Sodalis-like symbiont was also detected in these two aphids, and Gilliamella was found in some samples of M. sacchari. We further assessed the significant variation in symbiont communities within the two aphid species, geographical regions and host specialization using statistical and ordination analyses. Geography was an important factor in shaping the symbiont community structure in these oligophagous aphids. Furthermore, the strong geographical influence may be related to specific environmental factors, especially temperature, among different regions. These findings extend our knowledge of the significance of geography and its associated environmental conditions in the symbiont community structure associated with oligophagous aphids.

RevDate: 2021-09-10

Preethish-Kumar V, Shah A, Polavarapu K, et al (2021)

Disrupted structural connectome and neurocognitive functions in Duchenne muscular dystrophy: classifying and subtyping based on Dp140 dystrophin isoform.

Journal of neurology [Epub ahead of print].

OBJECTIVE: Neurocognitive disabilities in Duchenne muscular dystrophy (DMD) children beginning in early childhood and distal DMD gene deletions involving disruption of Dp140 isoform are more likely to manifest significant neurocognitive impairments. MRI data analysis techniques like brain-network metrics can provide information on microstructural integrity and underlying pathophysiology.

METHODS: A prospective study on 95 participants [DMD = 57, and healthy controls (HC) = 38]. The muscular dystrophy functional rating scale (MDFRS) scores, neuropsychology batteries, and multiplex ligand-dependent probe amplification (MLPA) testing were used for clinical assessment, IQ estimation, and genotypic classification. Diffusion MRI and network-based statistics were used to analyze structural connectomes at various levels and correlate with clinical markers.

RESULTS: Motor and executive sub-networks were extracted and analyzed. Out of 57 DMD children, 23 belong to Dp140 + and 34 to Dp140- subgroup. Motor disabilities are pronounced in Dp140- subgroup as reflected by lower MDFRS scores. IQ parameters are significantly low in all-DMD cases; however, the Dp140- has specifically lowest scores. Significant differences were observed in global efficiency, transitivity, and characteristic path length between HC and DMD. Subgroup analysis demonstrates that the significance is mainly driven by participants with Dp140- than Dp140 + isoform. Finally, a random forest classifier model illustrated an accuracy of 79% between HC and DMD and 90% between DMD- subgroups.

CONCLUSIONS: Current findings demonstrate structural network-based characterization of abnormalities in DMD, especially prominent in Dp140-. Our observations suggest that participants with Dp140 + have relatively intact connectivity while Dp140- show widespread connectivity alterations at global, nodal, and edge levels. This study provides valuable insights supporting the genotype-phenotype correlation of brain-behavior involvement in DMD children.

RevDate: 2021-09-10

Kiefer JST, Batsukh S, Bauer E, et al (2021)

Author Correction: Inhibition of a nutritional endosymbiont by glyphosate abolishes mutualistic benefit on cuticle synthesis in Oryzaephilus surinamensis.

Communications biology, 4(1):1079.

RevDate: 2021-09-10

Büttner H, Niehs SP, Vandelannoote K, et al (2021)

Bacterial endosymbionts protect beneficial soil fungus from nematode attack.

Proceedings of the National Academy of Sciences of the United States of America, 118(37):.

Fungi of the genus Mortierella occur ubiquitously in soils where they play pivotal roles in carbon cycling, xenobiont degradation, and promoting plant growth. These important fungi are, however, threatened by micropredators such as fungivorous nematodes, and yet little is known about their protective tactics. We report that Mortierella verticillata NRRL 6337 harbors a bacterial endosymbiont that efficiently shields its host from nematode attacks with anthelmintic metabolites. Microscopic investigation and 16S ribosomal DNA analysis revealed that a previously overlooked bacterial symbiont belonging to the genus Mycoavidus dwells in M. verticillata hyphae. Metabolic profiling of the wild-type fungus and a symbiont-free strain obtained by antibiotic treatment as well as genome analyses revealed that highly cytotoxic macrolactones (CJ-12,950 and CJ-13,357, syn necroxime C and D), initially thought to be metabolites of the soil-inhabiting fungus, are actually biosynthesized by the endosymbiont. According to comparative genomics, the symbiont belongs to a new species (Candidatus Mycoavidus necroximicus) with 12% of its 2.2 Mb genome dedicated to natural product biosynthesis, including the modular polyketide-nonribosomal peptide synthetase for necroxime assembly. Using Caenorhabditis elegans and the fungivorous nematode Aphelenchus avenae as test strains, we show that necroximes exert highly potent anthelmintic activities. Effective host protection was demonstrated in cocultures of nematodes with symbiotic and chemically complemented aposymbiotic fungal strains. Image analysis and mathematical quantification of nematode movement enabled evaluation of the potency. Our work describes a relevant role for endofungal bacteria in protecting fungi against mycophagous nematodes.

RevDate: 2021-09-10
CmpDate: 2021-09-10

Yoshida S, YJ Kee (2021)

Large-scale sequencing paves the way for genomic and genetic analyses in parasitic plants.

Current opinion in biotechnology, 70:248-254.

Parasitic plants pose a serious agricultural threat, but are also precious resources for valuable metabolites. The heterotrophic nature of these plants has resulted in the development of several morphological and physiological features that are of evolutionary significance. Recent advances in large-scale sequencing technology have provided insights into the evolutionary and molecular mechanisms of plant parasitism. Genome sequencing has revealed gene losses and horizontal gene transfers in parasitic plants. Mobile signals traveling between the parasite and host may have contributed to the increased fitness of parasitic life styles. Transcriptome analyses implicate shared processes among various parasitic species and the establishment of functional analysis is beginning to reveal molecular mechanisms during host and parasite interactions.

RevDate: 2021-09-10
CmpDate: 2021-09-10

Duchenne F, Fontaine C, Teulière E, et al (2021)

Phenological traits foster persistence of mutualistic networks by promoting facilitation.

Ecology letters, 24(10):2088-2099.

Morphological and phenological traits are key determinants of the structure of mutualistic networks. Both traits create forbidden links, but phenological traits can also decouple interaction in time. While such difference likely affects the indirect effects among species and consequently network persistence, it remains overlooked. Here, using a dynamic model, we show that networks structured by phenology favour facilitation over competition within guilds of pollinators and plants, thereby increasing network persistence, while the contrary holds for networks structured by morphology. We further show that such buffering of competition by phenological traits mostly beneficiate to specialists, the most vulnerable species otherwise, which propagate the most positive effects within guilds and promote nestedness. Our results indicate that beyond trophic mismatch, phenological shifts such as those induced by climate change are likely to affect indirect effects within mutualistic assemblages, with consequences for biodiversity.

RevDate: 2021-09-09

Decelle J, Veronesi G, LeKieffre C, et al (2021)

Subcellular architecture and metabolic connection in the planktonic photosymbiosis between Collodaria (radiolarians) and their microalgae.

Environmental microbiology [Epub ahead of print].

Photosymbiosis is widespread and ecologically important in the oceanic plankton but remains poorly studied. Here, we used multimodal subcellular imaging to investigate the photosymbiosis between colonial Collodaria and their microalga dinoflagellate (Brandtodinium). We showed that this symbiosis is very dynamic whereby symbionts interact with different host cells via extracellular vesicles within the colony. 3D electron microscopy revealed that the photosynthetic apparatus of the microalgae was more voluminous in symbiosis compared to free-living while the mitochondria volume was similar. Stable isotope probing coupled with NanoSIMS showed that carbon and nitrogen were stored in the symbiotic microalga in starch granules and purine crystals, respectively. Nitrogen was also allocated to the algal nucleolus. In the host, low 13 C transfer was detected in the Golgi. Metal mapping revealed that intracellular iron concentration was similar in free-living and symbiotic microalgae (ca 40 ppm) and two-fold higher in the host, whereas copper concentration increased in symbionts and was detected in the host cell and extracellular vesicles. Sulfur concentration was around two times higher in symbionts (chromatin and pyrenoid) than their host. This study improves our understanding on the functioning of this oceanic photosymbiosis and paves the way for more studies to further assess its biogeochemical significance. This article is protected by copyright. All rights reserved.

RevDate: 2021-09-09
CmpDate: 2021-09-09

Epihov DZ, Saltonstall K, Batterman SA, et al (2021)

Legume-microbiome interactions unlock mineral nutrients in regrowing tropical forests.

Proceedings of the National Academy of Sciences of the United States of America, 118(11):.

Legume trees form an abundant and functionally important component of tropical forests worldwide with N2-fixing symbioses linked to enhanced growth and recruitment in early secondary succession. However, it remains unclear how N2-fixers meet the high demands for inorganic nutrients imposed by rapid biomass accumulation on nutrient-poor tropical soils. Here, we show that N2-fixing trees in secondary Neotropical forests triggered twofold higher in situ weathering of fresh primary silicates compared to non-N2-fixing trees and induced locally enhanced nutrient cycling by the soil microbiome community. Shotgun metagenomic data from weathered minerals support the role of enhanced nitrogen and carbon cycling in increasing acidity and weathering. Metagenomic and marker gene analyses further revealed increased microbial potential beneath N2-fixers for anaerobic iron reduction, a process regulating the pool of phosphorus bound to iron-bearing soil minerals. We find that the Fe(III)-reducing gene pool in soil is dominated by acidophilic Acidobacteria, including a highly abundant genus of previously undescribed bacteria, Candidatus Acidoferrum, genus novus. The resulting dependence of the Fe-cycling gene pool to pH determines the high iron-reducing potential encoded in the metagenome of the more acidic soils of N2-fixers and their nonfixing neighbors. We infer that by promoting the activities of a specialized local microbiome through changes in soil pH and C:N ratios, N2-fixing trees can influence the wider biogeochemical functioning of tropical forest ecosystems in a manner that enhances their ability to assimilate and store atmospheric carbon.

RevDate: 2021-09-07
CmpDate: 2021-09-07

Dang H, Zhang T, Li G, et al (2020)

Root-associated endophytic bacterial community composition and structure of three medicinal licorices and their changes with the growing year.

BMC microbiology, 20(1):291.

BACKGROUND: The dried roots and rhizomes of medicinal licorices are widely used worldwide as a traditional medicinal herb, which are mainly attributed to a variety of bioactive compounds that can be extracted from licorice root. Endophytes and plants form a symbiotic relationship, which is an important source of host secondary metabolites.

RESULTS: In this study, we used high-throughput sequencing technology and high-performance liquid chromatography to explore the composition and structure of the endophytic bacterial community and the content of bioactive compounds (glycyrrhizic acid, liquiritin and total flavonoids) in different species of medicinal licorices (Glycyrrhiza uralensis, Glycyrrhiza glabra, and Glycyrrhiza inflata) and in different planting years (1-3 years). Our results showed that the contents of the bioactive compounds in the roots of medicinal licorices were not affected by the species, but were significantly affected by the main effect growing year (1-3) (P < 0.05), and with a trend of stable increase in the contents observed with each growing year. In 27 samples, a total of 1,979,531 effective sequences were obtained after quality control, and 2432 effective operational taxonomic units (OTUs) were obtained at 97% identity. The phylum Proteobacteria, Actinobacteria, Bacteroidetes and Firmicutes, and the genera unified-Rhizobiaceae, Pseudomonas, Novosphingobium, and Pantoea were significantly dominant in the 27 samples. Distance-based redundancy analysis (db-RDA) showed that the content of total flavonoids explained the differences in composition and distribution of endophytic bacterial communities in roots of cultivated medicinal liquorices to the greatest extent. Total soil salt was the most important factor that significantly affected the endophytic bacterial community in soil factors, followed by ammonium nitrogen and nitrate nitrogen. Among the leaf nutrition factors, leaf water content had the most significant effect on the endophytic bacterial community, followed by total phosphorus and total potassium.

CONCLUSIONS: This study not only provides information on the composition and distribution of endophytic bacteria in the roots of medicinal licorices, but also reveals the influence of abiotic factors on the community of endophytic bacteria and bioactive compounds, which provides a reference for improving the quality of licorice.

RevDate: 2021-09-09
CmpDate: 2021-09-09

Di Genio S, Wang LH, Meng PJ, et al (2021)

"Symbio-Cryobank": Toward the Development of a Cryogenic Archive for the Coral Reef Dinoflagellate Symbiont Symbiodiniaceae.

Biopreservation and biobanking, 19(1):91-93.

RevDate: 2021-09-08

Agarwal R, Gupta M, Antony A, et al (2021)

In Vitro Studies Reveal that Pseudomonas, from Odontotermes obesus Colonies, can Function as a Defensive Mutualist as it Prevents the Weedy Fungus While Keeping the Crop Fungus Unaffected.

Microbial ecology [Epub ahead of print].

Insects that farm monocultures of fungi are canonical examples of nutritional symbiosis as well as independent evolution of agriculture in non-human animals. But just like in human agriculture, these fungal crops face constant threat of invasion by weeds which, if unchecked, take over the crop fungus. In fungus-growing termites, the crop fungus (Termitomyces) faces such challenges from the weedy fungus Pseudoxylaria. The mechanism by which Pseudoxylaria is suppressed is not known. However, evidence suggests that some bacterial secondary symbionts can serve as defensive mutualists by preventing the growth of Pseudoxylaria. However, such secondary symbionts must possess the dual, yet contrasting, capabilities of suppressing the weedy fungus while keeping the growth of the crop fungus unaffected. This study describes the isolation, identification, and culture-dependent estimation of the roles of several such putative defensive mutualists from the colonies of the wide-spread fungus-growing termite from India, Odontotermes obesus. From the 38 bacterial cultures tested, a strain of Pseudomonas showed significantly greater suppression of the weedy fungus than the crop fungus. Moreover, a 16S rRNA pan-microbiome survey, using the Nanopore platform, revealed Pseudomonas to be a part of the core microbiota of O. obesus. A meta-analysis of microbiota composition across different species of Odontotermes also confirms the widespread prevalence of Pseudomonas within this termite. These lines of evidence indicate that Pseudomonas could be playing the role of defensive mutualist within Odontotermes.

RevDate: 2021-09-08

Xie J, Yan QL, T Zhang (2020)

[Temporal effects of thinning on the composition and growth of regenerated woody plants in Larix kaempferi plantations].

Ying yong sheng tai xue bao = The journal of applied ecology, 31(8):2481-2490.

Understanding the temporal effects of thinning on the composition and growth of regene-rated broadleaved woody species in coniferous plantations can provide profound references for promoting the conversion of monoculture plantations into mixed conifer-broadleaved forests, which could solve the problem that the production and ecological functions of monoculture plantations cannot be balanced. We compared the composition of regenerated woody plant species in Larix kaempferi plantation with short-term (1-3 years), medium-term (4-9 years) and long-term (>9 years) after thinning. Furthermore, we selected three regenerated tree species with higher importance value and reciprocal symbiosis with L. kaempferi, which differed in shade tolerance, including shade-intolerant species Quercus mongolica, intermediate shade-tolerant species Acer mono, and shade-tolerant species Tilia mandschurica. We analyzed the relationships between light conditions (i.e., canopy density) and the growth (i.e., base diameter and height) of those species in L. kaempferi plantation with different terms after thinning. The results showed that 46 species of regene-rated broadleaved woody plants were recorded in thinned plantations. The common and dominant tree in different terms after thinning was A. mono, and the shrub species were Lonicera japonica and Euonymus alatus. With the increasing time after thinning, species richness of regenerated trees decreased, but the ratio of tree to shrub species increased and the intermediate shade-tolerant tree species took the dominant position. The temporal effect of thinning on the growth of three tree species was affected by shade tolerance ability. Basal diameter and height of T. mandschurica were higher than those of Q. mongolica and A. mono. With the increases of time after thinning, basal diameter of T. mandschurica and height of A. mono were more sensitive to light, indicating that there were respectively "a shade tolerance strategy" and "a shade avoidance strategy" to adapt to the post-thinning environment. The effects of thinning on the composition and growth of regenerated broadleaved woody species in L. kaempferi plantations were significantly time-sensitive. When deve-loping thinning measures to promote the regeneration of broadleaved trees in plantations, we should consider to extend the thinning interval appropriately to ensure the growth of broadleaved tree seedlings (e.g., T. mandschurica and A. mono) and accelerate their migration into the canopy layer. This would promote the formation of mixed conifer-broadleaved forests and eventually realize the sustainable development of plantations.

RevDate: 2021-09-08

Hom EFY, AS Penn (2021)

Symbiosis and the Anthropocene.

Symbiosis (Philadelphia, Pa.) pii:794 [Epub ahead of print].

Recent human activity has profoundly transformed Earth biomes on a scale and at rates that are unprecedented. Given the central role of symbioses in ecosystem processes, functions, and services throughout the Earth biosphere, the impacts of human-driven change on symbioses are critical to understand. Symbioses are not merely collections of organisms, but co-evolved partners that arise from the synergistic combination and action of different genetic programs. They function with varying degrees of permanence and selection as emergent units with substantial potential for combinatorial and evolutionary innovation in both structure and function. Following an articulation of operational definitions of symbiosis and related concepts and characteristics of the Anthropocene, we outline a basic typology of anthropogenic change (AC) and a conceptual framework for how AC might mechanistically impact symbioses with select case examples to highlight our perspective. We discuss surprising connections between symbiosis and the Anthropocene, suggesting ways in which new symbioses could arise due to AC, how symbioses could be agents of ecosystem change, and how symbioses, broadly defined, of humans and "farmed" organisms may have launched the Anthropocene. We conclude with reflections on the robustness of symbioses to AC and our perspective on the importance of symbioses as ecosystem keystones and the need to tackle anthropogenic challenges as wise and humble stewards embedded within the system.

RevDate: 2021-09-08
CmpDate: 2021-09-08

Gichuhi J, Khamis F, Van den Berg J, et al (2020)

Influence of inoculated gut bacteria on the development of Bactrocera dorsalis and on its susceptibility to the entomopathogenic fungus, Metarhizium anisopliae.

BMC microbiology, 20(1):321.

BACKGROUND: Symbiotic interactions between insects and bacteria have been associated with a vast variety of physiological, ecological and evolutionary consequences for the host. A wide range of bacterial communities have been found in association with the oriental fruit fly, Bactrocera dorsalis (Hendel) (Diptera: Tephritidae), an important pest of cultivated fruit in most regions of the world. We evaluated the diversity of gut bacteria in B. dorsalis specimens from several populations in Kenya and investigated the roles of individual bacterial isolates in the development of axenic (germ-free) B. dorsalis fly lines and their responses to the entomopathogenic fungus, Metarhizium anisopliae.

RESULTS: We sequenced 16S rRNA to evaluate microbiomes and coupled this with bacterial culturing. Bacterial isolates were mono-associated with axenic B. dorsalis embryos. The shortest embryonic development period was recorded in flies with an intact gut microbiome while the longest period was recorded in axenic fly lines. Similarly, larval development was shortest in flies with an intact gut microbiome, in addition to flies inoculated with Providencia alcalifaciens. Adult B. dorsalis flies emerging from embryos that had been mono-associated with a strain of Lactococcus lactis had decreased survival when challenged with a standard dosage of M. anisopliae ICIPE69 conidia. However, there were no differences in survival between the germ-free lines and flies with an intact microbiome.

CONCLUSIONS: These findings will contribute to the selection of probiotics used in artificial diets for B. dorsalis rearing and the development of improved integrated pest management strategies based on entomopathogenic fungi.

RevDate: 2021-09-08
CmpDate: 2021-09-08

Sun S, Li F, Xu X, et al (2020)

Study on the community structure and function of symbiotic bacteria from different growth and developmental stages of Hypsizygus marmoreus.

BMC microbiology, 20(1):311.

BACKGROUND: The symbiotic bacteria associated with edible fungi are valuable microbial resources worthy of in-depth exploration. It is important to analyze the community structure and succession of symbiotic bacteria in mushrooms. This can assist in the isolation of growth-promoting strains that have an essential relationship with the cultivation cycle as well as the agronomic traits and yields of fruiting bodies.

RESULTS: In all of the samples from cultivation bags of Hypsizygus marmoreus, 34 bacterial phyla were detected. Firmicutes was the most abundant bacterial phylum (78.85%). The genus Serratia showed an exponential increase in abundance in samples collected from the cultivation bags in the mature period, reaching a peak abundance of 55.74% and the dominant symbiotic flora. The most predominant strain was Serratia odorifera HZSO-1, and its abundance increased with the amount of hyphae of H. marmoreus. Serratia odorifera HZSO-1 could reside in the hyphae of H. marmoreus, promote growth and development, shorten the fruiting cycle by 3-4 days, and further increase the fruiting body yield by 12%.

CONCLUSIONS: This study is a pioneering demonstration of the community structure of the symbiotic microbiota and bacteria-mushroom interaction in the growth and development of edible fungi. This work lays a theoretical foundation to improve the industrial production of mushrooms with symbiotic bacteria as assisting agents.

RevDate: 2021-09-07

Shinkura R (2021)

Therapeutic immunoglobulin A antibody for dysbiosis-related diseases.

International immunology pii:6366027 [Epub ahead of print].

Dysbiosis is alterations in the microbial composition compared with a healthy microbiota and often features a reduction in gut microbial diversity and a change in microbial taxa. Dysbiosis, especially in the gut, has also been proposed to play a crucial role in the pathogenesis of a wide variety of diseases, including inflammatory bowel disease, colorectal cancer, cardiovascular disease, obesity, diabetes and multiple sclerosis. A body of evidence has shown that intestinal polymeric immunoglobulin A (IgA) antibodies are important to regulate the gut microbiota as well as to exclude pathogenic bacteria or viral infection such as influenza and SARS-CoV-2 (severe acute respiratory syndrome coronavirus 2) at mucosal sites. Since the 1970s, trials for oral administration of therapeutic IgA or IgG have been performed mainly to treat infectious enteritis caused by pathogenic Escherichia coli or Clostridium difficile. However, few of them has been successfully developed as a clinical application up to now. In addition to the protective function against intestinal pathogens, IgA is well known to modulate the gut commensal microbiota leading to symbiosis. Nevertheless, the development of therapeutic IgA drugs to treat dysbiosis is not progressing. In this review, the advantages of therapeutic IgA antibodies and the problems for their development will be discussed.

RevDate: 2021-09-07

Muñoz VL, Figueredo MS, Reinoso H, et al (2021)

Role of ethylene in effective establishment of the peanut-bradyrhizobia symbiotic interaction.

Plant biology (Stuttgart, Germany) [Epub ahead of print].

Ethylene has been implicated in nitrogen fixing symbioses in legumes, where rhizobial invasion occurs via infection threads (IT). In the symbiosis between peanut (Arachis hypogaea L.) and bradyrhizobia, the bacteria penetrate the root cortex intercellularly and IT are not formed. Little attention has been paid to the function of ethylene in the establishment of this symbiosis. The aim of this article is to evaluate whether ethylene plays a role in the development of this symbiotic interaction and the participation of Nod Factors (NF) in the regulation of ethylene signalling. Manipulation of ethylene in peanut was accomplished by application of 1-aminocyclopropane-1-carboxylic acid (ACC), which mimics applied ethylene, or AgNO3, which blocks ethylene responses. To elucidate the participation of NF in the regulation of ethylene signalling, we inoculated plants with a mutant isogenic rhizobial strain unable to produce NF and evaluated the effect of AgNO3 on gene expression of NF and ethylene responsive signalling pathways. Data revealed that ethylene perception is required for the formation of nitrogen-fixing nodules, while addition of ACC does not affect peanut symbiotic performance. This phenotypic evidence is in agreement with transcriptomic data from genes involved in symbiotic and ethylene signalling pathways. NF seem to modulate the expression of ethylene signalling genes. Unlike legumes infected through IT formation, ACC addition to peanut does not adversely affect nodulation, but ethylene perception is required for establishment of this symbiosis. Evidence for the contribution of NF to the modulation of ethylene-inducible defence gene expression is provided.

RevDate: 2021-09-07

Sonel E, Gür Ş, T Eren (2021)

Analysis of factors affecting industrial symbiosis collaboration.

Environmental science and pollution research international [Epub ahead of print].

The rapidly increasing population causes an increase in consumption amounts day by day. This leads to negative effects such as the reduction of limited resources. In order to eliminate or reduce such negative effects, sustainable approaches are adopted for the future. Industrial symbiosis is one of these sustainable approaches. Industrial symbiosis is when two or more economic enterprises operating independently of each other form beneficial partnerships. In this study, the factors affecting industrial symbiosis collaboration were determined by literature review and by analyzing these factors; it is aimed to eliminate inefficiencies and to ensure the sustainability of established relations. The criteria determined are weighted with the Analytical Network Process method, which is one of the multi-criteria decision-making methods, and it is aimed to calculate the degree of importance and priority.

RevDate: 2021-09-07

Bitomský M, Pakeman RJ, Schaefer H, et al (2021)

Mycorrhizal status is a poor predictor of the distribution of herbaceous species along the gradient of soil nutrient availability in coastal and grassland habitats.

Mycorrhiza [Epub ahead of print].

Plant mycorrhizal status (a trait indicating the ability to form mycorrhizas) can be a useful plant trait for predicting changes in vegetation influenced by increased fertility. Mycorrhizal fungi enhance nutrient uptake and are expected to provide a competitive advantage for plants growing in nutrient-poor soils; while in nutrient-rich soils, mycorrhizal symbiosis may be disadvantageous. Some studies in natural systems have shown that mycorrhizal plants can be more frequent in P and N-poor soils (low nutrient availability) or Ca and Mg-high (high pH) soils, but empirical support is still not clear. Using vegetation and soil data from Scottish coastal habitats, and Latvian and Czech grasslands, we examined whether there is a link between plant mycorrhizal status and plant-available P, N, Ca and Mg. We performed the max test analysis (to examine the central tendency) and a combination of quantile regression and meta-analysis (to examine tendencies in different quantiles) on both community and plant species data combined with plant phylogenies. We consistently found no changes in mycorrhizal status at the community and species levels along the gradients of plant-available P, N, Ca and Mg in the central tendency and in almost all quantiles across all datasets. Thus, we found no support for the hypotheses that herbaceous species which are able to form mycorrhizas are more frequent in nutrient-poor and high pH environments. Obligatory, facultatively and non-mycorrhizal herbaceous species appear to assemble randomly along the gradients of nutrient availability in several European herbaceous habitats, suggesting that all these strategies perform similarly under non-extreme soil nutrient conditions.

RevDate: 2021-09-07

Tang N, Lebreton A, Xu W, et al (2021)

Transcriptome Profiling Reveals Differential Gene Expression of Secreted Proteases and Highly Specific Gene Repertoires Involved in Lactarius-Pinus Symbioses.

Frontiers in plant science, 12:714393.

Ectomycorrhizal fungi establish a mutualistic symbiosis in roots of most woody plants. The molecular underpinning of ectomycorrhizal development was only explored in a few lineages. Here, we characterized the symbiotic transcriptomes of several milkcap species (Lactarius, Russulales) in association with different pine hosts. A time-course study of changes in gene expression during the development of L. deliciosus-Pinus taeda symbiosis identified 6 to 594 differentially expressed fungal genes at various developmental stages. Up- or down-regulated genes are involved in signaling pathways, nutrient transport, cell wall modifications, and plant defenses. A high number of genes coding for secreted proteases, especially sedolisins, were induced during root colonization. In contrast, only a few genes encoding mycorrhiza-induced small secreted proteins were identified. This feature was confirmed in several other Lactarius species in association with various pines. Further comparison among all these species revealed that each Lactarius species encodes a highly specific symbiotic gene repertoire, a feature possibly related to their host-specificity. This study provides insights on the genetic basis of symbiosis in an ectomycorrhizal order, the Russulales, which was not investigated so far.

RevDate: 2021-09-07

Mendoza-Suárez M, Andersen SU, Poole PS, et al (2021)

Competition, Nodule Occupancy, and Persistence of Inoculant Strains: Key Factors in the Rhizobium-Legume Symbioses.

Frontiers in plant science, 12:690567.

Biological nitrogen fixation by Rhizobium-legume symbioses represents an environmentally friendly and inexpensive alternative to the use of chemical nitrogen fertilizers in legume crops. Rhizobial inoculants, applied frequently as biofertilizers, play an important role in sustainable agriculture. However, inoculants often fail to compete for nodule occupancy against native rhizobia with inferior nitrogen-fixing abilities, resulting in low yields. Strains with excellent performance under controlled conditions are typically selected as inoculants, but the rates of nodule occupancy compared to native strains are rarely investigated. Lack of persistence in the field after agricultural cycles, usually due to the transfer of symbiotic genes from the inoculant strain to naturalized populations, also limits the suitability of commercial inoculants. When rhizobial inoculants are based on native strains with a high nitrogen fixation ability, they often have superior performance in the field due to their genetic adaptations to the local environment. Therefore, knowledge from laboratory studies assessing competition and understanding how diverse strains of rhizobia behave, together with assays done under field conditions, may allow us to exploit the effectiveness of native populations selected as elite strains and to breed specific host cultivar-rhizobial strain combinations. Here, we review current knowledge at the molecular level on competition for nodulation and the advances in molecular tools for assessing competitiveness. We then describe ongoing approaches for inoculant development based on native strains and emphasize future perspectives and applications using a multidisciplinary approach to ensure optimal performance of both symbiotic partners.

RevDate: 2021-09-07

Prazeres M, Roberts TE, Ramadhani SF, et al (2021)

Diversity and flexibility of algal symbiont community in globally distributed larger benthic foraminifera of the genus Amphistegina.

BMC microbiology, 21(1):243.

BACKGROUND: Understanding the specificity and flexibility of the algal symbiosis-host association is fundamental for predicting how species occupy a diverse range of habitats. Here we assessed the algal symbiosis diversity of three species of larger benthic foraminifera from the genus Amphistegina and investigated the role of habitat and species identity in shaping the associated algal community.

RESULTS: We used next-generation sequencing to identify the associated algal community, and DNA barcoding to identify the diatom endosymbionts associated with species of A. lobifera, A. lessonii, and A. radiata, collected from shallow habitats (< 15 m) in 16 sites, ranging from the Mediterranean Sea to French Polynesia. Next-generation sequencing results showed the consistent presence of Ochrophyta as the main algal phylum associated with all species and sites analysed. A significant proportion of phylotypes were classified as Chlorophyta and Myzozoa. We uncovered unprecedented diversity of algal phylotypes found in low abundance, especially of the class Bacillariophyta (i.e., diatoms). We found a significant influence of sites rather than host identity in shaping algal communities in all species. DNA barcoding revealed the consistent presence of phylotypes classified within the order Fragilariales as the diatoms associated with A. lobifera and A. lessonii, while A. radiata specimens host predominately diatoms of the order Triceratiales.

CONCLUSIONS: We show that local habitat is the main factor influencing the overall composition of the algal symbiont community. However, host identity and the phylogenetic relationship among hosts is relevant in shaping the specific endosymbiont diatom community, suggesting that the relationship between diatom endosymbiont and hosts plays a crucial role in the evolutionary history of the genus Amphistegina. The capacity of Amphistegina species to associate with a diverse array of diatoms, and possibly other algal groups, likely underpins the ecological success of these crucial calcifying organisms across their extensive geographic range.

RevDate: 2021-09-07

Chrostek E, Martins N, Marialva MS, et al (2021)

Wolbachia-Conferred Antiviral Protection Is Determined by Developmental Temperature.

mBio [Epub ahead of print].

Wolbachia is a maternally transmitted bacterium that is widespread in arthropods and filarial nematodes and confers strong antiviral protection in Drosophila melanogaster and other arthropods. Wolbachia-transinfected Aedes aegypti mosquitoes are currently being deployed to fight transmission of dengue and Zika viruses. However, the mechanism of antiviral protection and the factors influencing are still not fully understood. Here, we show that temperature modulates Wolbachia-conferred protection in Drosophila melanogaster. Temperature after infection directly impacts Drosophila C virus (DCV) replication and modulates Wolbachia protection. At higher temperatures, viruses proliferate more and are more lethal, while Wolbachia confers lower protection. Strikingly, host developmental temperature is a determinant of Wolbachia-conferred antiviral protection. While there is strong protection when flies develop from egg to adult at 25°C, the protection is highly reduced or abolished when flies develop at 18°C. However, Wolbachia-induced changes during development are not sufficient to limit virus-induced mortality, as Wolbachia is still required to be present in adults at the time of infection. This developmental effect is general, since it was present in different host genotypes, Wolbachia variants, and upon infection with different viruses. Overall, we show that Wolbachia-conferred antiviral protection is temperature dependent, being present or absent depending on the environmental conditions. This interaction likely impacts Wolbachia-host interactions in nature and, as a result, frequencies of host and symbionts in different climates. Dependence of Wolbachia-mediated pathogen blocking on developmental temperature could be used to dissect the mechanistic bases of protection and influence the deployment of Wolbachia to prevent transmission of arboviruses. IMPORTANCE Insects are often infected with beneficial intracellular bacteria. The bacterium Wolbachia is extremely common in insects and can protect them from pathogenic viruses. This effect is being used to prevent transmission of dengue and Zika viruses by Wolbachia-infected mosquitoes. To understand the biology of insects in the wild, we need to discover which factors affect Wolbachia-conferred antiviral protection. Here, we show that the temperature at which insects develop from eggs to adults can determine the presence or absence of antiviral protection. The environment, therefore, strongly influences this insect-bacterium interaction. Our work may help to provide insights into the mechanism of viral blocking by Wolbachia, deepen our understanding of the geographical distribution of host and symbiont, and incentivize further research on the temperature dependence of Wolbachia-conferred protection for control of mosquito-borne disease.

RevDate: 2021-09-07
CmpDate: 2021-09-07

Bosse MA, Silva MBD, Oliveira NGRM, et al (2021)

Physiological impact of flavonoids on nodulation and ureide metabolism in legume plants.

Plant physiology and biochemistry : PPB, 166:512-521.

Legume plants from Fabaceae family (phylogenetic group composed by three subfamilies: Caesalpinioideae, Mimosoideae, and Papilionoideae) can fix atmospheric nitrogen (N2) into ammonia (NH3) by the symbiotic relationship with rhizobia bacteria. These bacteria respond chemotactically to certain compounds released by plants such as sugars, amino acids and organic acids. Root secretion of isoflavonoids acts as inducers for nod genes in rhizobia and ABC transporters and ICHG (isoflavone conjugates hydrolyzing beta-glucosidase) at apoplast are related to the exudation of genistein and daidzein in soybean roots. Biological nitrogen fixation (BNF) occurs inside the nodule by the action of nitrogenase enzyme, which fixes N2 into NH3, which is converted into ureides (allantoin and allantoic acid). In this review, we bring together the latest findings on flavonoids biosynthesis and ureide metabolism in several legume plant species. We emphasize how flavonoids induce nod genes in rhizobia, affecting chemotaxis, nodulation, ureide production, growth and yield of legume plants. Mainly, isoflavonoids daidzein and genistein are responsible for nod genes activation in the rhizobia bacteria. Flavonoids also play an important role during nodule organogenesis by acting as auxin transporter inhibitors in root cells, especially in indeterminate nodules. The ureides are the main N transport form in tropical legumes and they are catabolized in leaves and other sink tissues to produce amino acids and proteins needed for plant growth and yield.

RevDate: 2021-09-07
CmpDate: 2021-09-07

Weis AM, JL Round (2021)

Microbiota-antibody interactions that regulate gut homeostasis.

Cell host & microbe, 29(3):334-346.

Immunoglobulin A (IgA) is the most abundant antibody at mucosal surfaces and has been the subject of many investigations involving microbiota research in the last decade. Although the classic functions of IgA include neutralization of harmful toxins, more recent investigations have highlighted an important role for IgA in regulating the composition and function of the commensal microbiota. Multiple reviews have comprehensively covered the literature that describes recent, novel mechanisms of action of IgA and development of the IgA response within the intestine. Here we focus on how the interaction between IgA and the microbiota promotes homeostasis with the host to prevent disease.

RevDate: 2021-09-07
CmpDate: 2021-09-07

Becattini S, Sorbara MT, Kim SG, et al (2021)

Rapid transcriptional and metabolic adaptation of intestinal microbes to host immune activation.

Cell host & microbe, 29(3):378-393.e5.

The gut microbiota produces metabolites that regulate host immunity, thereby impacting disease resistance and susceptibility. The extent to which commensal bacteria reciprocally respond to immune activation, however, remains largely unexplored. Herein, we colonized mice with four anaerobic symbionts and show that acute immune responses result in dramatic transcriptional reprogramming of these commensals with minimal changes in their relative abundance. Transcriptomic changes include induction of stress-response mediators and downregulation of carbohydrate-degrading factors such as polysaccharide utilization loci (PULs). Flagellin and anti-CD3 antibody, two distinct immune stimuli, induced similar transcriptional profiles, suggesting that commensal bacteria detect common effectors or activate shared pathways when facing different host responses. Immune activation altered the intestinal metabolome within 6 hours, decreasing luminal short-chain fatty acid and increasing aromatic metabolite concentrations. Thus, intestinal bacteria, prior to detectable shifts in community composition, respond to acute host immune activation by rapidly changing gene transcription and immunomodulatory metabolite production.

RevDate: 2021-09-07
CmpDate: 2021-09-07

Gao S, Kong Y, Yu J, et al (2020)

Isolation of axenic cyanobacterium and the promoting effect of associated bacterium on axenic cyanobacterium.

BMC biotechnology, 20(1):61.

BACKGROUND: Harmful cyanobacterial blooms have attracted wide attention all over the world as they cause water quality deterioration and ecosystem health issues. Microcystis aeruginosa associated with a large number of bacteria is one of the most common and widespread bloom-forming cyanobacteria that secret toxins. These associated bacteria are considered to benefit from organic substrates released by the cyanobacterium. In order to avoid the influence of associated heterotrophic bacteria on the target cyanobacteria for physiological and molecular studies, it is urgent to obtain an axenic M. aeruginosa culture and further investigate the specific interaction between the heterotroph and the cyanobacterium.

RESULTS: A traditional and reliable method based on solid-liquid alternate cultivation was carried out to purify the xenic cyanobacterium M. aeruginosa FACHB-905. On the basis of 16S rDNA gene sequences, two associated bacteria named strain B905-1 and strain B905-2, were identified as Pannonibacter sp. and Chryseobacterium sp. with a 99 and 97% similarity value, respectively. The axenic M. aeruginosa FACHB-905A (Microcystis 905A) was not able to form colonies on BG11 agar medium without the addition of strain B905-1, while it grew well in BG11 liquid medium. Although the presence of B905-1 was not indispensable for the growth of Microcystis 905A, B905-1 had a positive effect on promoting the growth of Microcystis 905A.

CONCLUSIONS: The associated bacteria were eliminated by solid-liquid alternate cultivation method and the axenic Microcystis 905A was successfully purified. The associated bacterium B905-1 has the potentiality to promote the growth of Microcystis 905A. Moreover, the purification technique for cyanobacteria described in this study is potentially applicable to a wider range of unicellular cyanobacteria.

RevDate: 2021-09-07
CmpDate: 2021-09-07

Jiménez RR, Alvarado G, Sandoval J, et al (2020)

Habitat disturbance influences the skin microbiome of a rediscovered neotropical-montane frog.

BMC microbiology, 20(1):292.

BACKGROUND: The skin microbiome serves as a first line defense against pathogens in vertebrates. In amphibians, it has the potential to protect against the chytrid fungus Batrachochytrium dendrobatis (Bd), a likely agent of amphibian declines. Alteration of the microbiome associated with unfavorable environmental changes produced by anthropogenic activities may make the host more susceptible to pathogens. Some amphibian species that were thought to be "extinct" have been rediscovered years after population declines in the late 1980s probably due to evolved Bd-resistance and are now threatened by anthropogenic land-use changes. Understanding the effects of habitat disturbance on the host skin microbiome is relevant for understanding the health of these species, along with its susceptibility to pathogens such as Bd. Here, we investigate the influence of habitat alteration on the skin bacterial communities as well as specifically the putative Bd-inhibitory bacterial communities of the montane frog Lithobates vibicarius. This species, after years of not being observed, was rediscovered in small populations inhabiting undisturbed and disturbed landscapes, and with continuous presence of Bd.

RESULTS: We found that cutaneous bacterial communities of tadpoles and adults differed between undisturbed and disturbed habitats. The adults from disturbed habitats exhibited greater community dispersion than those from undisturbed habitats. We observed a higher richness of putative Bd-inhibitory bacterial strains in adults from disturbed habitats than in those from undisturbed habitats, as well as a greater number of these potential protective bacteria with a high relative abundance.

CONCLUSIONS: Our findings support the microbial "Anna Karenina principle", in which disturbance is hypothesized to cause greater microbial dispersion in communities, a so-called dysbiosis, which is a response of animal microbiomes to stress factors that decrease the ability of the host or its microbiome to regulate community composition. On the positive side, the high richness and relative abundance of putative Bd-inhibitory bacteria may indicate the development of a defense mechanism that enhances Bd-protection, attributed to a co-occurrence of more than 30-years of host and pathogen in these disturbed habitats. Our results provide important insight into the influence of human-modified landscapes on the skin microbiome and health implications of Bd-survivor species.

RevDate: 2021-09-06

Yang Z, Du H, Xing X, et al (2021)

A small heat shock protein, GmHSP17.9, from nodule confers symbiotic nitrogen fixation and seed yield in soybean.

Plant biotechnology journal [Epub ahead of print].

Legume-rhizobia symbiosis enables biological nitrogen fixation to improve crop production for sustainable agriculture. Small heat shock proteins (sHSPs) are involved in multiple environmental stresses and plant development processes. However, the role of sHSPs in nodule development in soybean remains largely unknown. In the present study, we identified a nodule-localized sHSP, called GmHSP17.9, in soybean, which was markedly upregulated during nodule development. GmHSP17.9 was specifically expressed in the infected regions of the nodules. GmHSP17.9 overexpression and RNAi in transgenic composite plants and loss of function in CRISPR-Cas9 gene-editing mutant plants in soybean resulted in remarkable alterations in nodule number, nodule fresh weight, nitrogenase activity, contents of poly β-hydroxybutyrate bodies (PHBs), ureide, and total nitrogen content, which caused significant changes in plant growth and seed yield. GmHSP17.9 was also found to act as a chaperone for its interacting partner, GmNOD100, a sucrose synthase in soybean nodules which was also preferentially expressed in the infected zone of nodules, similar to GmHSP17.9. Functional analysis of GmNOD100 in composite transgenic plants revealed that GmNOD100 played an essential role in soybean nodulation. The hsp17.9 lines showed markedly more reduced sucrose synthase activity, lower contents of UDP-glucose and acetyl coenzyme A (acetyl-CoA), and decreased activity of succinic dehydrogenase (SDH) in the tricarboxylic acid (TCA) cycle in nodules due to the missing interaction with GmNOD100. Our findings reveal an important role and an unprecedented molecular mechanism of sHSPs in nodule development and nitrogen fixation in soybean.

RevDate: 2021-09-06

Pashkova TM, Morozova NV, Kuzmin MD, et al (2021)

[Characteristics of the pathogenic potential of Escherichia coli isolated from patients with calculous pyelonephritis].

Urologiia (Moscow, Russia : 1999).

OBJECTIVE: Comparative phenotypic and genetic assessment of the pathogenic potential of E. coli strains isolated from patients with calculous pyelonephritis.

MATERIALS AND METHODS: 78 strains of E. coli isolated from urine of patients with calculous pyelonephritis in the acute phase (n=58) and in the remission phase (n=20). Escherichia were investigated for the presence of virulence genes papA, pap EF, papGII; afa, bma E, iutA, fyuA, feoB, kspMTII, usp multiplex PCR using selected primers. Phenotypically determined the ability to biofilm formation, antilysozyme, antihemoglobin, anticytokine, adhesive and sIgA-protease activity E. coli.

RESULTS: The virulent potential of Escherichia coli at the pheno- and genotype levels was characterized. In strains of E. coli isolated from the urine of patients in the remission phase, the ability to form biofilms was more often and with high values of the trait; and in strains isolated in relapse - adhesive activity, the ability to inactivate pro- and anti-inflammatory cytokines, antihemoglobin activity, and genes encoding aphimbrial adhesin (afa), responsible for the synthesis of siderophore aerobactin (iutA), transporting bivalent iron (feoB).

CONCLUSION: The revealed differences in the pheno- and genotypic profiles between the cultures of Escherichia coli isolated from patients with calculous pyelonephritis in the phases of exacerbation and remission make it possible to differentiate the isolated strain and predict the course of the infectious-inflammatory process.

RevDate: 2021-09-06

Rimal Y, Gochhait S, A Bisht (2021)

Data interpretation and visualization of COVID-19 cases using R programming.

Informatics in medicine unlocked pii:S2352-9148(21)00188-X [Epub ahead of print].

Background: Data analysis and visualization are essential for exploring and communicating medical research findings, especially when working with COVID records.

Results: Data on COVID-19 diagnosed cases and deaths from December 2019 is collected automatically from,, and the Multidisciplinary Digital Publishing Institute (MDPI). We have developed an application for data visualization and analysis of several indicators to follow the SARS-CoV-2 epidemic using Statista, Data Hub, and MDPI data from densely populated countries like the United States, Japan, and India using R programming.

Conclusions: The COVID19-World online web application systematically produces daily updated country-specific data visualization and analysis of the SARS-CoV-2 epidemic worldwide. The application will help with a better understanding of the SARS-CoV-2 epidemic worldwide.

RevDate: 2021-09-06

Gould AL, Fritts-Penniman A, A Gaisiner (2021)

Museum Genomics Illuminate the High Specificity of a Bioluminescent Symbiosis for a Genus of Reef Fish.

Frontiers in ecology and evolution, 9:.

Symbiotic relationships between bioluminescent bacteria and fishes have evolved multiple times across hundreds of fish taxa, but relatively little is known about the specificity of these associations and how stable they are over host generations. This study describes the degree of specificity of a bioluminescent symbiosis between cardinalfishes in the genus Siphamia and luminous bacteria in the Vibrio family. Primarily using museum specimens, we investigated the codivergence of host and symbiont and test for patterns of divergence that correlate with both biogeography and time. Contrary to expectations, we determined that the light organ symbionts of all 14 Siphamia species examined belong to one genetic clade of Photobacterium mandapamensis (Clade II), indicating that the association is highly specific and conserved throughout the host genus. Thus, we did not find evidence of codivergence among hosts and symbionts. We did observe that symbionts hosted by individuals sampled from colder water regions were more divergent, containing more than three times as many single nucleotide polymorphisms than the rest of the symbionts examined. Overall, our findings indicate that the symbiosis between Siphamia fishes and P. mandapamensis Clade II has been highly conserved across host taxa and over a broad geographic range despite the facultative nature of the bacterial symbiont. We also present a new approach to simultaneously recover genetic information from a bacterial symbiont and its vertebrate host from formalin-fixed specimens, enhancing the utility of museum collections.

RevDate: 2021-09-06

Jadhav S, V Nema (2021)

HIV-Associated Neurotoxicity: The Interplay of Host and Viral Proteins.

Mediators of inflammation, 2021:1267041.

HIV-1 can incite activation of chemokine receptors, inflammatory mediators, and glutamate receptor-mediated excitotoxicity. The mechanisms associated with such immune activation can disrupt neuronal and glial functions. HIV-associated neurocognitive disorder (HAND) is being observed since the beginning of the AIDS epidemic due to a change in the functional integrity of cells from the central nervous system (CNS). Even with the presence of antiretroviral therapy, there is a decline in the functioning of the brain especially movement skills, noticeable swings in mood, and routine performance activities. Under the umbrella of HAND, various symptomatic and asymptomatic conditions are categorized and are on a rise despite the use of newer antiretroviral agents. Due to the use of long-lasting antiretroviral agents, this deadly disease is becoming a manageable chronic condition with the occurrence of asymptomatic neurocognitive impairment (ANI), symptomatic mild neurocognitive disorder, or HIV-associated dementia. In-depth research in the pathogenesis of HIV has focused on various mechanisms involved in neuronal dysfunction and associated toxicities ultimately showcasing the involvement of various pathways. Increasing evidence-based studies have emphasized a need to focus and explore the specific pathways in inflammation-associated neurodegenerative disorders. In the current review, we have highlighted the association of various HIV proteins and neuronal cells with their involvement in various pathways responsible for the development of neurotoxicity.

RevDate: 2021-09-06

Gupta MM, DHS Richardson (2021)

Editorial: Anthropogenic impacts on symbiotic systems.

RevDate: 2021-09-05

Bishop C, Jurga E, L Graham (2021)

Patterns of bacterial diversity in embryonic capsules of the spotted salamander Ambystoma maculatum: an expanding view of a symbiosis.

FEMS microbiology ecology pii:6364358 [Epub ahead of print].

The unicellular green alga, Oophila amblystomatis, populates egg capsules of the spotted salamander Ambystoma maculatum. This nutrient-exchange mutualism is widely perceived as a bipartite interaction but the presence and contributing effects of bacteria to this symbiosis are unknown. We used standard cultivation techniques and amplicon sequencing of the V4/V5 region of 16S rRNA gene to identify and compare diversity of bacterial taxa in embryonic capsules to that in the aquatic breeding habitat. Our sampling regime allowed us to investigate diversity among individual capsules of an egg mass and between two ponds and sampling years. Capsules contain much lower diversity of bacteria than pond water and spatial and temporal variation in intracapsular and pond bacterial diversity was observed. Despite this variation, sequences corresponding to species in the orders Burkholderiales and Oligoflexales and were either prevalent, abundant, or both. Isolates most commonly recovered from capsules were closely related to species in the genus Herbaspirillum (Burkholderiaceae); other isolates were pseudomonads, but in all cases are closely related to known vascular plant-associated species. We conclude that, despite observed variation, there are bacterial taxa whose presence is held in common spatially and temporally among capsules and that the symbiosis between O. amblystomatis and A. maculatum may involve these taxa.

RevDate: 2021-09-06
CmpDate: 2021-09-06

Huot L, Bigourdan A, Pagès S, et al (2020)

Partner-specific induction of Spodoptera frugiperda immune genes in response to the entomopathogenic nematobacterial complex Steinernema carpocapsae-Xenorhabdus nematophila.

Developmental and comparative immunology, 108:103676.

The Steinernema carpocapsae-Xenorhabdus nematophila association is a nematobacterial complex used in biological control of insect crop pests. The infection success of this dual pathogen strongly depends on its interactions with the host's immune system. Here, we used the lepidopteran pest Spodoptera frugiperda to analyze the respective impact of each partner in the induction of its immune responses. First, we used previously obtained RNAseq data to construct the immunome of S. frugiperda and analyze its induction. We then selected representative genes to study by RT-qPCR their induction kinetics and specificity after independent injections of each partner. We showed that both X. nematophila and S. carpocapsae participate in the induction of stable immune responses to the complex. While X. nematophila mainly induces genes classically involved in antibacterial responses, S. carpocapsae induces lectins and genes involved in melanization and encapsulation. We discuss putative relationships between these differential inductions and the pathogen immunosuppressive strategies.

RevDate: 2021-09-04

Stahlhut KN, Dowell JA, Temme AA, et al (2021)

Genetic control of arbuscular mycorrhizal colonization by Rhizophagus intraradices in Helianthus annuus (L.).

Mycorrhiza [Epub ahead of print].

Plant symbiosis with arbuscular mycorrhizal (AM) fungi provides many benefits, including increased nutrient uptake, drought tolerance, and belowground pathogen resistance. To develop a better understanding of the genetic architecture of mycorrhizal symbiosis, we conducted a genome-wide association study (GWAS) of this plant-fungal interaction in cultivated sunflower. A diversity panel of cultivated sunflower (Helianthus annuus L.) was phenotyped for root colonization under inoculation with the AM fungus Rhizophagus intraradices. Using a mixed linear model approach with a high-density genetic map, we identified genomic regions that are likely associated with R. intraradices colonization in sunflower. Additionally, we used a set of twelve diverse lines to assess the effect that inoculation with R. intraradices has on dried shoot biomass and macronutrient uptake. Colonization among lines in the mapping panel ranged from 0-70% and was not correlated with mycorrhizal growth response, shoot phosphorus response, or shoot potassium response among the Core 12 lines. Association mapping yielded three single-nucleotide polymorphisms (SNPs) that were significantly associated with R. intraradices colonization. This is the first study to use GWAS to identify genomic regions associated with AM colonization in an Asterid eudicot species. Three genes of interest identified from the regions containing these SNPs are likely related to plant defense.

RevDate: 2021-09-04

Qiu X, Gao T, Yang J, et al (2021)

Water-Soluble Humic Materials Modulating Metabolism and Triggering Stress Defense in Sinorhizobium fredii.

Microbiology spectrum, 9(1):e0029321.

Bacteria have evolved a series of mechanisms to maintain their survival and reproduction in changeable and stressful environments. In-depth understanding of these mechanisms can allow for better developing and utilizing of bacteria with various biological functions. In this study, we found that water-soluble humic materials (WSHM), a well-known environment-friendly plant growth biostimulant, significantly promoted the free-living growth and survival of Sinorhizobium fredii CCBAU45436 in a bell-shaped, dose-dependent manner, along with more-efficient carbon source consumption and relief of medium acidification. By using RNA-Seq analysis, a total of 1,136 genes significantly up-/downregulated by external addition of WSHM were identified under test conditions. These differentially expressed genes (DEGs) were enriched in functional categories related to carbon/nitrogen metabolism, cellular stress response, and genetic information processing. Further protein-protein interaction (PPI) network analysis and reverse genetic engineering indicated that WSHM might reprogram the transcriptome through inhibiting the expression of key hub gene rsh, which encodes a bifunctional enzyme catalyzing synthesis and hydrolysis of the "magic spot" (p)ppGpp. In addition, the root colonization and viability in soil of S. fredii CCBAU45436 were increased by WSHM. These findings provide us with new insights into how WSHM benefit bacterial adaptations and demonstrate great application value to be a unique inoculant additive. IMPORTANCE Sinorhizobium fredii CCBAU45436 is a highly effective, fast-growing rhizobium that can establish symbiosis with multiple soybean cultivars. However, it is difficult to maintain the high-density effective viable cells in the rhizobial inoculant for the stressful conditions during production, storage, transport, and application. Here, we showed that WSHM greatly increased the viable cells of S. fredii CCBAU45436 in culture, modulating metabolism and triggering stress defense. The root colonization and viability in soil of S. fredii CCBAU45436 were also increased by WSHM. Our results shed new insights into the effects of WSHM on bacteria and the importance of metabolism and stress defense during the bacteria's whole life. In addition, the functional mechanism of WSHM may provide candidate genes for improving environmental adaptability and application potential of bacteria through genetic engineering.

RevDate: 2021-09-03

Côté IM, SJ Brandl (2021)

Functional niches of cleanerfish species are mediated by habitat use, cleaning intensity, and client selectivity.

The Journal of animal ecology [Epub ahead of print].

An animal's functional niche is a complex, multidimensional construct, mediated by an individual's morphology, physiology, and behaviour. Behavioural aspects of the niche can be difficult to quantify, as their expression is often subtle and tailored to an infinite number of different situations that involve sophisticated mechanisms such as mutualisms, species dominance, or fear effects. The extreme diversity of tropical fish assemblages has led to extensive debate over the extent to which species differ in their resource use and functional role. Ectoparasite removal by cleanerfish species is considered a behaviourally complex interspecific interaction in vertebrates, but differences in the services rendered by various species of cleanerfish, and potential consequences for the range of clients (i.e., resources) they attract, have rarely been examined. Here, we quantify differences among three coexisting species of morphologically similar cleaner wrasses (Labroides bicolor, L. dimidiatus, and L. pectoralis) in the global centre of marine biodiversity, the Coral Triangle. We found no clear taxonomic partitioning of clients among cleanerfishes. However, the three cleanerfish species exhibited distinct habitat preferences, and differed in their cleaning intensity: L. bicolor serviced the fewest species and clients, while L. pectoralis serviced the most clients and spent the most time cleaning. Accordingly, L. pectoralis showed no preference for clients based on client size or abundance, while both L. bicolor and L. dimidiatus had a higher likelihood of interacting with clients based on their size (larger client species in L. bicolor, smaller client species in L. dimidiatus) and abundance (more abundant client species for both). Our results suggest that the services rendered by the three species of cleanerfishes differ in their spatial availability, quality, and selectivity, thus permitting the coexistence of these species despite their ecological similarity. This, in turn, creates a complex seascape of species-specific cleaning services that underpins crucial biotic interactions in the ocean's most diverse ecosystem.

RevDate: 2021-09-03

Dusselier M, Ke Q, Khalil I, et al (2021)

A Cooperative OSDA Blueprint for Highly Siliceous Faujasite Zeolite Catalysts with Enhanced Acidity Accessibility.

Angewandte Chemie (International ed. in English) [Epub ahead of print].

A cooperative OSDA strategy is demonstrated, leading to novel high-silica FAU zeolites with a large potential for disruptive acid catalysis. In bottom-up synthesis, the symbiosis of choline ion (Ch +) and 15-crown-5 (CE) was evidenced, in a form of full occupation of the sodalite (sod) cages with the trans Ch + conformer, induced by the CE presence. CE itself occupied the supercages along with additional gauche Ch + , but in synthesis without CE, no trans was found. The cooperation, and thus the fraction of trans Ch + , was closely related to the Si/Al ratio, a key measure for FAU stability and acidity. As such, a bottom-up handle for lowering the Al-content of FAU and tuning its acid site distribution is shown. A mechanistic study demonstrated that forming sod cages with trans Ch + is key to the nucleation of high-silica FAU zeolites. The materials showed superior performances to commercial FAU zeolites and those synthesized without cooperation, in the catalytic degradation of polyethylene.

RevDate: 2021-09-03

Bolejko A, Andersson BT, Debess J, et al (2021)

Facilitators for and barriers to radiography research in public healthcare in Nordic countries.

Radiography (London, England : 1995) pii:S1078-8174(21)00115-2 [Epub ahead of print].

INTRODUCTION: It has been suggested that the future of diagnostic imaging relies on engagement in research and evidence-based practice. This implies a role transition from a clinical radiographer to a clinical radiographer-researcher. Clinical radiographers' stimuli for engaging in research in Nordic countries are unknown. This study aimed to address this gap.

METHODS: Cross-sectional data collection via an online questionnaire on facilitators for and barriers to participation in radiography research was carried out among 507 clinical radiographers in public healthcare in the Nordic countries: Denmark, Finland, Norway and Sweden.

RESULTS: Support from colleagues (odds ratio [OR] 2.62) and other professionals (OR 2.74), and self-esteem in research skills (OR ≥ 2.21), were facilitators for radiography research. Lack of knowledge and skills to conduct research (OR 2.48) was revealed to hinder radiographers' participation in research. The absence of a radiography research culture in the workplace explained non-participation in research (OR 1.75).

CONCLUSION: This study revealed significant factors for clinical radiographers' participation in research.

IMPLICATIONS FOR PRACTICE: A strategy for establishing a radiography research culture in healthcare is proposed that is novel for the context. Management support for knowledge development and activity leading to inter-professional research projects across knowledge fields, provision of a radiography research lead and acknowledgement of radiography research among colleagues signify the establishment of the culture. These prerequisites might provide a paradigm change towards not only the symbiosis of a clinical radiographer and an autonomous researcher but also a partner who adds radiography research to evidence-based practice in diagnostic imaging.

RevDate: 2021-09-03
CmpDate: 2021-09-03

Mao Q, Wu W, Huang L, et al (2020)

Insect Bacterial Symbiont-Mediated Vitellogenin Uptake into Oocytes To Support Egg Development.

mBio, 11(6):.

Many insect species, such as aphids, leafhoppers, planthoppers, and whiteflies harbor obligate bacterial symbionts that can be transovarially transmitted to offspring through the oocytes of female insects. Whether obligate bacterial symbionts can carry important molecules/resources to the embryos to support egg development is still unknown. Here, we show that the vitellogenin (Vg) precursor of rice leafhopper Nephotettix cincticeps is biosynthesized by the fat body, secreted into the hemolymph and subsequently cleaved into the 35- and 178-kDa subunits, whereas only the 178-kDa subunit is taken up by the leading end of oocytes in a receptor-dependent manner or moves into the posterior pole of the terminal oocyte in association with obligate bacterial symbiont "Candidatus Nasuia deltocephalinicola" (hereafter Nasuia) in a receptor-independent manner. Furthermore, the 178-kDa Vg subunit can directly interact with a surface channel molecule (porin) on the envelope of Nasuia, allowing Vg to enter bacterial cytoplasm. Thus, Vg can hitchhike the ancient oocyte entry path of Nasuia, the common obligate symbiont of leafhoppers. Knocking down a Nasuia growth-related protein expression or treatment with porin antibody strongly prevents the ability of Nasuia to carry Vgs into oocytes and impair insect egg development. Nasuia-carried Vgs provide at least 20% of the total Vgs in the developing eggs. We anticipate that the bacterial symbiont-mediated Vg uptake into oocytes to support efficient egg development may be a common pattern shared by many insects.IMPORTANCE Many insects harbor obligate bacterial symbionts that can be vertically transmitted to offspring by female insects through eggs. Here, we report that leafhopper vitellogenin (Vg) recognizes and binds a surface channel molecule (porin) on the envelope of obligate bacterial symbiont Nasuia, which potentially induces the opening of porin channels for Vg to access the cytoplasm of Nasuia Thus, Vg can exploit bacterial symbionts as the independent carriers into the oocytes. Such Nasuia-carried Vg contents support efficient insect egg development. Thus, our findings indicate that insects have evolved strategies to exploit the symbionts for carrying additional Vgs to guarantee optimal insect reproduction.

RevDate: 2021-09-02

Bizarria Júnior R, Pagnocca FC, A Rodrigues (2021)

Yeasts in the attine ant-fungus mutualism: diversity, functional roles, and putative biotechnological applications.

Yeast (Chichester, England) [Epub ahead of print].

Insects interact with a wide variety of yeasts, often providing a suitable substrate for their growth. Some yeast-insect interactions are tractable models for understanding the relationships between the symbionts. Attine ants are prominent insects on the Neotropics and have performed an ancient fungiculture of mutualistic basidiomycete fungi for more than 55-65 million years. Yeasts gain access to this sophisticated mutualism, prompting diversity, ecological, and biotechnological studies in this environment. We reviewed half a century research in this field, surveying for recurrent yeast taxa and their putative ecological roles in this environment. We found that previous studies mainly covered the yeast diversity from a small fraction of attine ants, being Saccharomycetales, Tremellales, and Trichosporonales as the most frequent yeast or yeast-like orders. Apiotrichum, Aureobasidium, Candida, Cutaneotrichosporon, Debaryomyces, Meyerozyma, Papiliotrema, Rhodotorula, Trichomonascus, and Trichosporon are the most frequent recovered genera. On the other hand, yeast's ecological role on attine ant-fungus mutualism only tapped the tip of the iceberg. Previous established hypotheses in the literature cover the production of lignocellulosic enzymes, chemical detoxification, and fungus garden protection. Some of these roles have parallels in biotechnological processes. In conclusion, the attine ant environment has a hidden potential for studying yeast biodiversity, ecology, and biotechnology, which has been particularly unexplored considering the vast diversity of fungus-growing ants.

RevDate: 2021-09-02

Dauphin B, de Freitas Pereira M, Kohler A, et al (2021)

Cryptic genetic structure and copy-number variation in the ubiquitous forest symbiotic fungus Cenococcum geophilum.

Environmental microbiology [Epub ahead of print].

Ectomycorrhizal (ECM) fungi associated with plants constitute one of the most successful symbiotic interactions in forest ecosystems. ECM support trophic exchanges with host plants and are important factors for the survival and stress resilience of trees. However, ECM clades often harbour morpho-species and cryptic lineages, with weak morphological differentiation. How this relates to intraspecific genome variability and ecological functioning is poorly known. Here, we analysed 16 European isolates of the ascomycete Cenococcum geophilum, an extremely ubiquitous forest symbiotic fungus with no known sexual or asexual spore forming structures but with a massively enlarged genome. We carried out whole-genome sequencing to identify single-nucleotide polymorphisms. We found no geographic structure at the European scale but divergent lineages within sampling sites. Evidence for recombination was restricted to specific cryptic lineages. Lineage differentiation was supported by extensive copy-number variation. Finally, we confirmed heterothallism with a single MAT1 idiomorph per genome. Synteny analyses of the MAT1 locus revealed substantial rearrangements and a pseudogene of the opposite MAT1 idiomorph. Our study provides the first evidence for substantial genome-wide structural variation, lineage-specific recombination and low continent-wide genetic differentiation in C. geophilum. Our study provides a foundation for targeted analyses of intra-specific functional variation in this major symbiosis. This article is protected by copyright. All rights reserved.

RevDate: 2021-09-02

Fukudome M, Shimokawa Y, Hashimoto S, et al (2021)

Nitric Oxide Detoxification by Mesorhizobium loti Affects Root Nodule Symbiosis with Lotus japonicus.

Microbes and environments, 36(3):.

Root nodule symbiosis between legumes and rhizobia involves nitric oxide (NO) regulation by both the host plant and symbiotic rhizobia. However, the mechanisms by which the rhizobial control of NO affects root nodule symbiosis in Lotus japonicus are unknown. Therefore, we herein investigated the effects of enhanced NO removal by Mesorhizobium loti on symbiosis with L. japonicus. The hmp gene, which in Sinorhizobium meliloti encodes a flavohemoglobin involved in NO detoxification, was introduced into M. loti to generate a transconjugant with enhanced NO removal. The symbiotic phenotype of the transconjugant with L. japonicus was examined. The transconjugant showed delayed infection and higher nitrogenase activity in mature nodules than the wild type, whereas nodule senescence was normal. This result is in contrast to previous findings showing that enhanced NO removal in L. japonicus by class 1 phytoglobin affected nodule senescence. To evaluate differences in NO detoxification between M. loti and L. japonicus, NO localization in nodules was investigated. The enhanced expression of class 1 phytoglobin in L. japonicus reduced the amount of NO not only in infected cells, but also in vascular bundles, whereas that of hmp in M. loti reduced the amount of NO in infected cells only. This difference suggests that NO detoxification by M. loti exerts different effects in symbiosis than that by L. japonicus.

RevDate: 2021-09-02
CmpDate: 2021-09-02

Cusumano A, AN Volkoff (2021)

Influence of parasitoid-associated viral symbionts on plant-insect interactions and biological control.

Current opinion in insect science, 44:64-71.

Insect parasitoids have evolved symbiotic interactions with several viruses and thousands of parasitoid species have established mutualistic associations with polydnaviruses (PDVs). While PDVs have often been described as virulence factors allowing development of immature parasitoids inside their herbivore hosts, there is increasing awareness that PDVs can affect plant-insect interactions. We review recent literature showing that PDVs alter not only host physiology, but also feeding patterns and composition of herbivore's oral secretions. In turn PDV-induced changes in herbivore phenotype affect plant responses to herbivory with consequences ranging from differential expression of plant defense-related genes to wider ecological effects across multiple trophic levels. In this opinion paper we also highlight important missing gaps to fully understand the role of PDVs and other parasitoid-associated viral symbionts in a plant-insect interaction perspective. Because PDVs negatively impact performance and survival of herbivore pests, we conclude arguing that PDV genomes offer potential opportunities for biological control.

RevDate: 2021-09-02
CmpDate: 2021-09-02

Moon EK, Park SM, Chu KB, et al (2021)

Differentially Expressed Gene Profile of Acanthamoeba castellanii Induced by an Endosymbiont Legionella pneumophila.

The Korean journal of parasitology, 59(1):67-75.

Legionella pneumophila is an opportunistic pathogen that survives and proliferates within protists such as Acanthamoeba spp. in environment. However, intracellular pathogenic endosymbiosis and its implications within Acanthamoeba spp. remain poorly understood. In this study, RNA sequencing analysis was used to investigate transcriptional changes in A. castellanii in response to L. pneumophila infection. Based on RNA sequencing data, we identified 1,211 upregulated genes and 1,131 downregulated genes in A. castellanii infected with L. pneumophila for 12 hr. After 24 hr, 1,321 upregulated genes and 1,379 downregulated genes were identified. Gene ontology (GO) analysis revealed that L. pneumophila endosymbiosis enhanced hydrolase activity, catalytic activity, and DNA binding while reducing oxidoreductase activity in the molecular function (MF) domain. In particular, multiple genes associated with the GO term 'integral component of membrane' were downregulated during endosymbiosis. The endosymbiont also induced differential expression of various methyltransferases and acetyltransferases in A. castellanii. Findings herein are may significantly contribute to understanding endosymbiosis of L. pneumophila within A. castellanii.

RevDate: 2021-09-02
CmpDate: 2021-09-02

de Paula GT, Menezes C, Pupo MT, et al (2021)

Stingless bees and microbial interactions.

Current opinion in insect science, 44:41-47.

Stingless bees (Meliponini) are a monophyletic group of eusocial insects inhabiting tropical and subtropical regions. These insects represent the most abundant and diversified group of corbiculate bees. Meliponini mostly rely on fermentation by symbiont microbes to preserve honey and transform pollen in stored food. Bee nests harbor diverse microbiota that includes bacteria, yeasts, filamentous fungi, and viruses. These microorganisms may interact with the bees through symbiotic relationships, or they may act as food for the insects, or produce biomolecules that aid in the biotransformation of bee products, such as honey and bee bread. Certain microbial species can also produce antimicrobial compounds that inhibit opportunistic bee pathogens.

RevDate: 2021-09-02
CmpDate: 2021-09-02

Gavrin A, Rey T, Torode TA, et al (2020)

Developmental Modulation of Root Cell Wall Architecture Confers Resistance to an Oomycete Pathogen.

Current biology : CB, 30(21):4165-4176.e5.

The cell wall is the primary interface between plant cells and their immediate environment and must balance multiple functionalities, including the regulation of growth, the entry of beneficial microbes, and protection against pathogens. Here, we demonstrate how API, a SCAR2 protein component of the SCAR/WAVE complex, controls the root cell wall architecture important for pathogenic oomycete and symbiotic bacterial interactions in legumes. A mutation in API results in root resistance to the pathogen Phytophthora palmivora and colonization defects by symbiotic rhizobia. Although api mutant plants do not exhibit significant overall growth and development defects, their root cells display delayed actin and endomembrane trafficking dynamics and selectively secrete less of the cell wall polysaccharide xyloglucan. Changes associated with a loss of API establish a cell wall architecture with altered biochemical properties that hinder P. palmivora infection progress. Thus, developmental stage-dependent modifications of the cell wall, driven by SCAR/WAVE, are important in balancing cell wall developmental functions and microbial invasion.

RevDate: 2021-09-01

Wang P, Snijders R, Kohlen W, et al (2021)

Medicago SPX1 and SPX3 regulate phosphate homeostasis, mycorrhizal colonization, and arbuscule degradation.

The Plant cell pii:6361634 [Epub ahead of print].

To acquire sufficient mineral nutrients such as phosphate (Pi) from the soil, most plants engage in symbiosis with arbuscular mycorrhizal (AM) fungi. Attracted by plant-secreted strigolactones, the fungi colonize the roots and form highly-branched hyphal structures called arbuscules inside inner cortex cells. The host plant must control the different steps of this interaction to maintain its symbiotic nature. However, how plants sense the amount of Pi obtained from the fungus, and how this determines the arbuscule lifespan, are far from understood. Here, we show that Medicago truncatula SPX-domain containing proteins SPX1 and SPX3 regulate root Pi starvation responses, in part by interacting with PHOSPHATE RESPONSE REGULATOR2, as well as fungal colonization and arbuscule degradation. SPX1 and SPX3 are induced upon Pi starvation but become more restricted to arbuscule-containing cells upon the establishment of symbiosis. This induction in arbuscule-containing cells is associated with the presence of cis-regulatory AW-boxes and transcriptional regulation by the WRINKLED1-like transcription factor WRI5a. Under Pi-limiting conditions, SPX1 and SPX3 facilitate the expression of the strigolactone biosynthesis gene DWARF27, which could help explain the increased fungal branching in response to root exudates. Later, in arbuscule-containing cells, SPX1 and SPX3 redundantly control arbuscule degradation. Thus, SPX proteins play important roles as phosphate sensors to maintain a beneficial AM symbiosis.

RevDate: 2021-09-01

Sheng H, Weng R, He Y, et al (2021)

The coupling of mixotrophic denitrification, dissimilatory nitrate reduction to ammonium (DNRA) and anaerobic ammonium oxidation (anammox) promoting the start-up of anammox by addition of calcium nitrate.

Bioresource technology, 341:125822 pii:S0960-8524(21)01163-9 [Epub ahead of print].

This study discovered one nitrate-calcium-based anammox start-up pathway. Compared with control, the start-up time of anammox was saved by 33.3%, and the average total nitrogen removal efficiency increased from 29.6% to 53.7% during the start-up. Besides, the continuous nitrite accumulation (1.18 mg/L) and a marked increase in the relative abundance of denitrifying and anammox bacteria were observed in the only Ca(NO3)2-added group. These results suggested that calcium nitrate induced partial denitrification to provide nitrite for anammox. Additionally, the role of dissimilatory nitrate reduction to ammonium (DNRA) in the Ca(NO3)2-added systems also deserved attention, for the contribution of DNRA to nitrate removal as well as the relative abundance of DNRA bacteria were both increased for the Ca(NO3)2-added groups. These results suggested that a mutualistic symbiosis among denitrification, DNRA and anammox exists in the calcium nitrate-added systems, which may explain the reason for acceleration of anammox start-up by adding calcium nitrate.

RevDate: 2021-09-01

Fuentes Barrera GA, Gabarrell I Durany X, Rieradevall Pons J, et al (2021)

Trends in global research on industrial parks: A bibliometric analysis from 1996-2019.

Heliyon, 7(8):e07778 pii:S2405-8440(21)01881-8.

Industrial parks have been used to promote the economic development of countries. However, its rapid growth has generated environmental problems related to the depletion of natural resources and pollution. Consequently, the network analysis and the bibliometric analysis applied in this research generated qualitative and quantitative information from a systemic perspective on the thematic and community evolution of research on industrial parks (IP) performed to improve its negative environmental impact and reach sustainability. This study used the Web of Science (WoS) database from 1996 - 2019. The main trends and critical research points were identified in four periods of 6-year each. Social network analysis (SNA) was used to identify the intellectual structure main and the academic collaboration networks established among countries/territories, institutions, and authors. The most productive country in articles is currently China (882), however, when we consider the frequency of articles per million inhabitants, it ranks seventh. The WoS database grouped 63.6 ​% of the articles published in the subjects of "Environmental Sciences & Ecology", "Engineering", and "Science & Technology - Other Topics". Industrial Ecology (IE), Industrial Symbiosis (IS), and Circular Economy (CE) were the author keywords with the highest frequency, indicating that IP research has focused from these perspectives to promote the exchange of byproducts and to evaluate the performance and environmental impact of industrial areas through the use of methodologies such as carbon footprints, emergy analysis, and life cycle analysis (LCA). Finally, some themes were identified and proposed for future research based on analyzing research trends and hot spots from the literature review on industrial parks.


ESP Quick Facts

ESP Origins

In the early 1990's, Robert Robbins was a faculty member at Johns Hopkins, where he directed the informatics core of GDB — the human gene-mapping database of the international human genome project. To share papers with colleagues around the world, he set up a small paper-sharing section on his personal web page. This small project evolved into The Electronic Scholarly Publishing Project.

ESP Support

In 1995, Robbins became the VP/IT of the Fred Hutchinson Cancer Research Center in Seattle, WA. Soon after arriving in Seattle, Robbins secured funding, through the ELSI component of the US Human Genome Project, to create the original ESP.ORG web site, with the formal goal of providing free, world-wide access to the literature of classical genetics.

ESP Rationale

Although the methods of molecular biology can seem almost magical to the uninitiated, the original techniques of classical genetics are readily appreciated by one and all: cross individuals that differ in some inherited trait, collect all of the progeny, score their attributes, and propose mechanisms to explain the patterns of inheritance observed.

ESP Goal

In reading the early works of classical genetics, one is drawn, almost inexorably, into ever more complex models, until molecular explanations begin to seem both necessary and natural. At that point, the tools for understanding genome research are at hand. Assisting readers reach this point was the original goal of The Electronic Scholarly Publishing Project.

ESP Usage

Usage of the site grew rapidly and has remained high. Faculty began to use the site for their assigned readings. Other on-line publishers, ranging from The New York Times to Nature referenced ESP materials in their own publications. Nobel laureates (e.g., Joshua Lederberg) regularly used the site and even wrote to suggest changes and improvements.

ESP Content

When the site began, no journals were making their early content available in digital format. As a result, ESP was obliged to digitize classic literature before it could be made available. For many important papers — such as Mendel's original paper or the first genetic map — ESP had to produce entirely new typeset versions of the works, if they were to be available in a high-quality format.

ESP Help

Early support from the DOE component of the Human Genome Project was critically important for getting the ESP project on a firm foundation. Since that funding ended (nearly 20 years ago), the project has been operated as a purely volunteer effort. Anyone wishing to assist in these efforts should send an email to Robbins.

ESP Plans

With the development of methods for adding typeset side notes to PDF files, the ESP project now plans to add annotated versions of some classical papers to its holdings. We also plan to add new reference and pedagogical material. We have already started providing regularly updated, comprehensive bibliographies to the ESP.ORG site.

Electronic Scholarly Publishing
961 Red Tail Lane
Bellingham, WA 98226

E-mail: RJR8222 @

Papers in Classical Genetics

The ESP began as an effort to share a handful of key papers from the early days of classical genetics. Now the collection has grown to include hundreds of papers, in full-text format.

Digital Books

Along with papers on classical genetics, ESP offers a collection of full-text digital books, including many works by Darwin (and even a collection of poetry — Chicago Poems by Carl Sandburg).


ESP now offers a much improved and expanded collection of timelines, designed to give the user choice over subject matter and dates.


Biographical information about many key scientists.

Selected Bibliographies

Bibliographies on several topics of potential interest to the ESP community are now being automatically maintained and generated on the ESP site.

ESP Picks from Around the Web (updated 07 JUL 2018 )