Intergrated metagenomics and metabolomics analysis discovers nematicidal microbes, enzymes and metabolites from the plant rhizosphere microbiota

Abstract Background: Meloidogyne incognita infestation has led to huge economic loss worldwide. Nematicidal microorganisms provide an effective strategy to control M. incognita . In order to find microorganisms and new metabolites with high nematicidal activity, we collected M. incognita - infested tobacco rhizosphere soils and non-infested rhizosphere soils, and investigated functional genes, microbial community and network, and metabolites via metagenomics and metabolomics analyses. Results: Rhizosphere microbial composition, function, network and metabolites were altered accompanying with M . incognita infestation. Abundances of nematicidal microorganisms, metabolites, antibiotics and extracellular enzymes’ genes in the non-infested rhizosphere microbiota were higher than those in M. incognita -infested rhizosphere microbiota. Abundances of functions genes involved in secondary metabolites biosynthesis and carbohydrate transport and metabolism in the non-infested rhizosphere microbiota were higher than M. incognita -infested rhizosphere microbiota. Contents of 102 metabolites were different in the two rhizosphere microbiota. Contents of 35 metabolites (acetophenone, indole-3-acetic acid, etc.) in the non-infested rhizosphere microbiota were higher than those in M . incognita -infested rhizosphere microbiota. Acetophenone showed high nematicidal (LC 50 = 0.66 μg/ml) and repellent activities against M. incognita . Co-occurrence network analyses found Bacillus showed a stronger positive correlation with acetophenone. Nematicidal microorganisms were isolated from soils, and one isolate of B . amyloliquefaciens W1 produced acetophenone. Exposing J2 larvae of M. incognita to liquid culture filtrate of W1 resulted in a mortality rate of 98.8% after 24 h. Other isolates such as Aspergillus , Achromobacter , Acinetobacter , Bacillus , Burkholderia , Comamonas , Enterobacter , Lysobacter , Microbacterium , Paenibacillus , Pantoea , Pseudomonas , Streptomyces and Variovorax produced extracellular nematicidal enzymes. Conclusions: M eloidogyne incognita -infested rhizophere microbiota differed in microbial community composition, network structure, function genes and metabolites contents from the non-infested rhizosphere microbiota. Abundances of nematicidal microorganisms and metabolites, and genes involved in secondary metabolites biosynthesis and carbohydrate metabolism in the non-infested rhizosphere microbiota were higher than those in M . incognita -infested rhizosphere microbiota. Network complexity in M . incognita -infested rhizosphere microbiota was lower than that in non-infested rhizosphere microbiota. Keystone microorganisms were also different between these two networks. Acetophenone was identified as a new nematicidal compound with high activity to kill and repel M. incognita , and B. amyloliquefacens W1 isolated from non-infested soil produced acetophenone against M. incognita .

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Disentangling Responses of the Subsurface Microbiome to Wetland Status and Implications for Indicating Ecosystem Functions

Microorganisms ◽

10.3390/microorganisms9020211 ◽

2021 ◽

Vol 9 (2) ◽

pp. 211

Author(s):

Jie Gao ◽

Miao Liu ◽

Sixue Shi ◽

Ying Liu ◽

Yu Duan ◽

...

Keyword(s):

Microbial Community ◽

High Throughput Sequencing ◽

Carbon Fixation ◽

Microbial Community Composition ◽

Ecosystem Functions ◽

Microbial Composition ◽

Wetland Ecosystems ◽

Soil Microbial ◽

Geochemical Properties ◽

Microbial Groups

In this study, we analyzed microbial community composition and the functional capacities of degraded sites and restored/natural sites in two typical wetlands of Northeast China—the Phragmites marsh and the Carex marsh, respectively. The degradation of these wetlands, caused by grazing or land drainage for irrigation, alters microbial community components and functional structures, in addition to changing the aboveground vegetation and soil geochemical properties. Bacterial and fungal diversity at the degraded sites were significantly lower than those at restored/natural sites, indicating that soil microbial groups were sensitive to disturbances in wetland ecosystems. Further, a combined analysis using high-throughput sequencing and GeoChip arrays showed that the abundance of carbon fixation and degradation, and ~95% genes involved in nitrogen cycling were increased in abundance at grazed Phragmites sites, likely due to the stimulating impact of urine and dung deposition. In contrast, the abundance of genes involved in methane cycling was significantly increased in restored wetlands. Particularly, we found that microbial composition and activity gradually shifts according to the hierarchical marsh sites. Altogether, this study demonstrated that microbial communities as a whole could respond to wetland changes and revealed the functional potential of microbes in regulating biogeochemical cycles.

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Compared the Microbiota Profiles between Samples from Bronchoalveolar Lavage and Endotracheal Aspirates in Severe Pneumonia: A Real-World Experience

Journal of Clinical Medicine ◽

10.3390/jcm11020327 ◽

2022 ◽

Vol 11 (2) ◽

pp. 327

Author(s):

Yeong-Nan Cheng ◽

Wei-Chih Huang ◽

Chen-Yu Wang ◽

Pin-Kuei Fu

Keyword(s):

Microbial Community ◽

Bronchoalveolar Lavage ◽

Microbial Community Composition ◽

Severe Pneumonia ◽

Metagenomic Sequencing ◽

Microbial Composition ◽

Icu Patients ◽

Mechanically Ventilated ◽

The Difference ◽

New Onset

Lower respiratory tract sampling from endotracheal aspirate (EA) and bronchoalveolar lavage (BAL) are both common methods to identify pathogens in severe pneumonia. However, the difference between these two methods in microbiota profiles remains unclear. We compared the microbiota profiles of pairwise EA and BAL samples in ICU patients with respiratory failure due to severe pneumonia. We prospectively enrolled 50 ICU patients with new onset of pneumonia requiring mechanical ventilation. EA and BAL were performed on the first ICU day, and samples were analyzed for microbial community composition via 16S rRNA metagenomic sequencing. Pathogens were identified in culture medium from BAL samples in 21 (42%) out of 50 patients. No difference was observed in the antibiotic prescription pattern, ICU mortality, or hospital mortality between BAL-positive and BAL-negative patients. The microbiota profiles in the EA and BAL samples are similar with respect to diversity, microbial composition, and microbial community correlations. The antibiotic treatment regimen was rarely changed based on the BAL findings. The samples from BAL did not provide more information than EA in the microbiota profiles. We suggest that EA is more useful than BAL for microbiome identification in mechanically ventilated patients.

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PSI-10 Establishing a foundation to harvest the potential of the microbiome in poultry production

Journal of Animal Science ◽

10.1093/jas/skz258.594 ◽

2019 ◽

Vol 97 (Supplement_3) ◽

pp. 293-294

Author(s):

Camila S Marcolla ◽

Benjamin Willing

Keyword(s):

Microbial Community ◽

Gut Microbiota ◽

Community Composition ◽

Relative Abundance ◽

Microbial Community Composition ◽

Alpha Diversity ◽

Poultry Production ◽

Microbiota Composition ◽

Microbial Composition ◽

The Impact

Abstract This study aimed to characterize poultry microbiota composition in commercial farms using 16S rRNA sequencing. Animals raised in sanitized environments have lower survival rates when facing pathogenic challenges compared to animals naturally exposed to commensal organisms. We hypothesized that intensive rearing practices inadvertently impair chicken exposure to microbes and the establishment of a balanced gut microbiota. We compared gut microbiota composition of broilers (n = 78) and layers (n = 20) from different systems, including commercial intensive farms with and without in-feed antibiotics, organic free-range farms, backyard-raised chickens and chickens in an experimental farm. Microbial community composition of conventionally raised broilers was significantly different from antibiotic-free broilers (P = 0.012), from broilers raised outdoors (P = 0.048) and in an experimental farm (P = 0.006) (Fig1). Significant community composition differences were observed between antibiotic-fed and antibiotic-free chickens (Fig2). Antibiotic-free chickens presented higher alpha-diversity, higher relative abundance of Deferribacteres, Fusobacteria, Bacteroidetes and Actinobacteria, and lower relative abundance of Firmicutes, Clostridiales and Enterobacteriales than antibiotic-fed chickens (P < 0.001) (Fig3). Microbial community composition significantly changed as birds aged. In experimental farm, microbial community composition was significant different for 7, 21 and 35 day old broilers (P < 0.001), and alpha diversity increased from 7 to 21d (P < 0.024), but not from 21 to 35d; whereas, in organic systems, increases in alpha-diversity were observed from 7d to 21d, and from 21d to 35d (P < 0.05). Broilers and layers raised together showed no differences in microbiota composition and alpha diversity (P > 0.8). It is concluded that production practices consistently impact microbial composition, and that antibiotics significantly reduces microbial diversity. We are now exploring the impact of differential colonization in a controlled setting, to determine the impact of the microbes associated with extensively raised chickens. This study will support future research and the development of methods to isolate and introduce beneficial microbes to commercial systems.

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Effects of Actinomycete Secondary Metabolites on Sediment Microbial Communities

Applied and Environmental Microbiology ◽

10.1128/aem.02676-16 ◽

2016 ◽

Vol 83 (4) ◽

Cited By ~ 18

Author(s):

Nastassia V. Patin ◽

Michelle Schorn ◽

Kristen Aguinaldo ◽

Tommie Lincecum ◽

Bradley S. Moore ◽

...

Keyword(s):

Microbial Community ◽

Secondary Metabolites ◽

Microbial Communities ◽

Community Composition ◽

Marine Sediments ◽

Microbial Community Composition ◽

Amplicon Sequencing ◽

Next Generation ◽

Content Type ◽

Predatory Bacteria

ABSTRACT Marine sediments harbor complex microbial communities that remain poorly studied relative to other biomes such as seawater. Moreover, bacteria in these communities produce antibiotics and other bioactive secondary metabolites, yet little is known about how these compounds affect microbial community structure. In this study, we used next-generation amplicon sequencing to assess native microbial community composition in shallow tropical marine sediments. The results revealed complex communities comprised of largely uncultured taxa, with considerable spatial heterogeneity and known antibiotic producers comprising only a small fraction of the total diversity. Organic extracts from cultured strains of the sediment-dwelling actinomycete genus Salinispora were then used in mesocosm studies to address how secondary metabolites shape sediment community composition. We identified predatory bacteria and other taxa that were consistently reduced in the extract-treated mesocosms, suggesting that they may be the targets of allelopathic interactions. We tested related taxa for extract sensitivity and found general agreement with the culture-independent results. Conversely, several taxa were enriched in the extract-treated mesocosms, suggesting that some bacteria benefited from the interactions. The results provide evidence that bacterial secondary metabolites can have complex and significant effects on sediment microbial communities. IMPORTANCE Ocean sediments represent one of Earth's largest and most poorly studied biomes. These habitats are characterized by complex microbial communities where competition for space and nutrients can be intense. This study addressed the hypothesis that secondary metabolites produced by the sediment-inhabiting actinomycete Salinispora arenicola affect community composition and thus mediate interactions among competing microbes. Next-generation amplicon sequencing of mesocosm experiments revealed complex communities that shifted following exposure to S. arenicola extracts. The results reveal that certain predatory bacteria were consistently less abundant following exposure to extracts, suggesting that microbial metabolites mediate competitive interactions. Other taxa increased in relative abundance, suggesting a benefit from the extracts themselves or the resulting changes in the community. This study takes a first step toward assessing the impacts of bacterial metabolites on sediment microbial communities. The results provide insight into how low-abundance organisms may help structure microbial communities in ocean sediments.

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Hydrodynamic disturbance controls microbial community assembly and biogeochemical processes in coastal sediments

The ISME Journal ◽

10.1038/s41396-021-01111-9 ◽

2021 ◽

Author(s):

Ya-Jou Chen ◽

Pok Man Leung ◽

Perran L. M. Cook ◽

Wei Wen Wong ◽

Tess Hutchinson ◽

...

Keyword(s):

Microbial Community ◽

Community Assembly ◽

Microbial Community Composition ◽

Coastal Sediments ◽

Sediment Geochemistry ◽

Biogeochemical Processes ◽

Microbial Abundance ◽

Microbial Composition ◽

Hydrodynamic Disturbance ◽

Microbial Community Assembly

AbstractThe microbial community composition and biogeochemical dynamics of coastal permeable (sand) sediments differs from cohesive (mud) sediments. Tide- and wave-driven hydrodynamic disturbance causes spatiotemporal variations in oxygen levels, which select for microbial generalists and disrupt redox cascades. In this work, we profiled microbial communities and biogeochemical dynamics in sediment profiles from three sites varying in their exposure to hydrodynamic disturbance. Strong variations in sediment geochemistry, biogeochemical activities, and microbial abundance, composition, and capabilities were observed between the sites. Most of these variations, except for microbial abundance and diversity, significantly correlated with the relative disturbance level of each sample. In line with previous findings, metabolically flexible habitat generalists (e.g., Flavobacteriaceae, Woeseaiceae, Rhodobacteraceae) dominated in all samples. However, we present evidence that aerobic specialists such as ammonia-oxidizing archaea (Nitrosopumilaceae) were more abundant and active in more disturbed samples, whereas bacteria capable of sulfate reduction (e.g., uncultured Desulfobacterales), dissimilatory nitrate reduction to ammonium (DNRA; e.g., Ignavibacteriaceae), and sulfide-dependent chemolithoautotrophy (e.g., Sulfurovaceae) were enriched and active in less disturbed samples. These findings are supported by insights from nine deeply sequenced metagenomes and 169 derived metagenome-assembled genomes. Altogether, these findings suggest that hydrodynamic disturbance is a critical factor controlling microbial community assembly and biogeochemical processes in coastal sediments. Moreover, they strengthen our understanding of the relationships between microbial composition and biogeochemical processes in these unique environments.

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Community composition and development of the post-weaning piglet gut microbiome

10.21203/rs.3.rs-60981/v1 ◽

2020 ◽

Author(s):

Daniela Gaio ◽

Matthew Z DeMaere ◽

Kay Anantanawat ◽

Graeme J Eamens ◽

Michael Liu ◽

...

Keyword(s):

Microbial Community ◽

Gut Microbiota ◽

Community Composition ◽

Antibiotic Treatment ◽

Gut Microbiome ◽

Treatment Effects ◽

Sequence Data ◽

Microbial Community Composition ◽

Dominant Factor ◽

Microbial Composition

Abstract BackgroundEarly weaning and intensive farming practices predispose piglets to the development of infectious and often lethal diseases, against which antibiotics are used. Besides contributing to the build-up of antimicrobial resistance, antibiotics are known to modulate the gut microbial composition. Studies have previously investigated the effects of probiotics as alternatives to antibiotic treatment for the prevention of post-weaning diarrhea. In order to describe the post-weaning gut microbiota, and the effects of two probiotics formulations and of intramuscular antibiotic treatment on the gut microbiota, we processed over 800 faecal time-series samples from 126 piglets and 42 sows, generating over 8Tbp of metagenomic shotgun sequence data. Here we describe the animal trial procedures, the generation of our metagenomic dataset and the analysis of the microbial community composition using a phylogenetic framework.ResultsFactors such as age, litter effects, and breed, by significantly correlating with gut microbial community shifts, can be major confounding factors in the assessment of treatment effects. Intramuscular antibiotic treatment and probiotic treatments were found to correlate with alpha and beta diversity, as well as with a transient establishment of Mollicutes and Lactobacillales, respectively. We found the abundance of certain taxa to correlate with weight gain.ConclusionsOur findings demonstrate that breed, litter, and age, are important contributors to variation in the community composition, and that treatment effects of the antibiotic and probiotic treatments were subtle, while host age was the dominant factor in shaping the gut microbiota of piglets after weaning. The current study shows, by means of a phylogenetic diversity framework, that the post-weaning pig gut microbiome appears to follow a highly structured developmental program with characteristic post-weaning changes that can distinguish hosts that were born as little as two days apart in the second month of life.

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Spatial Diversity in Bacterial Communities across Barren and Vegetated, Native and Invasive, Coastal Dune Microhabitats

Diversity ◽

10.3390/d13110525 ◽

2021 ◽

Vol 13 (11) ◽

pp. 525

Author(s):

Brianna L. Boss ◽

Bianca R. Charbonneau ◽

Javier A. Izquierdo

Keyword(s):

Microbial Community ◽

Microbial Communities ◽

Community Composition ◽

Plant Species ◽

Bacterial Communities ◽

Environmental Gradients ◽

Microbial Community Composition ◽

Soil Microbial Communities ◽

Spatial Diversity ◽

Microbial Composition

The microbial community composition of coastal dunes can vary across environmental gradients, with the potential to impact erosion and deposition processes. In coastal foredunes, invasive plant species establishment can create and alter environmental gradients, thereby altering microbial communities and other ecogeomorphic processes with implications for storm response and management and conservation efforts. However, the mechanisms of these processes are poorly understood. To understand how changing microbial communities can alter these ecogeomorphic dynamics, one must first understand how soil microbial communities vary as a result of invasion. Towards this goal, bacterial communities were assessed spatially along foredune microhabitats, specifically in barren foredune toe and blowout microhabitats and in surrounding vegetated monocultures of native Ammophila breviligulata and invasive Carex kobomugi. Across dune microhabitats, microbial composition was more dissimilar in barren dune toe and blowout microhabitats than among the two plant species, but it did not appear that it would favor the establishment of one plant species over the other. However, the subtle differences between the microbial community composition of two species could ultimately aid in the success of the invasive species by reducing the proportions of bacterial genera associated exclusively with A. breviligulata. These results suggest that arrival time may be crucial in fostering microbiomes that would further the continued establishment and spread of either plant species.

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Temporal Analysis of the Microbial Community from the Crystallizer Ponds in Cabo Rojo, Puerto Rico, Using Metagenomics

Genes ◽

10.3390/genes10060422 ◽

2019 ◽

Vol 10 (6) ◽

pp. 422 ◽

Cited By ~ 5

Author(s):

Ricardo L. Couto-Rodríguez ◽

Rafael Montalvo-Rodríguez

Keyword(s):

Microbial Community ◽

Microbial Diversity ◽

Community Composition ◽

Ammonia Oxidation ◽

Microbial Community Composition ◽

Temporal Analysis ◽

Hypersaline Environment ◽

Hypersaline Environments ◽

Metabolic Processes ◽

Microbial Composition

The Cabo Rojo solar salterns are a hypersaline environment located in a tropical climate, where conditions remain stable throughout the year. These conditions can favor the establishment of steady microbial communities. Little is known about the microbial composition that thrives in hypersaline environments in the tropics. The main goal of this study was to assess the microbial diversity present in the crystallizer ponds of Cabo Rojo, in terms of structure and metabolic processes across time using metagenomic techniques. Three samplings (December 2014, March and July 2016) were carried out, where water samples (50 L each) were filtered through a Millipore pressurized filtering system. DNA was subsequently extracted using physical–chemical methods and sequenced using paired end Illumina technologies. The sequencing effort produced three paired end libraries with a total of 111,816,040 reads, that were subsequently assembled into three metagenomes. Out of the phyla detected, the microbial diversity was dominated in all three samples by Euryarchaeota, followed by Bacteroidetes and Proteobacteria. However, sample MFF1 (for Muestreo Final Fraternidad) exhibited a higher diversity, with 12 prokaryotic phyla detected at 34% NaCl (w/v), when compared to samples MFF2 and MFF3, which only exhibited three phyla. Precipitation events might be one of the contributing factors to the change in the microbial community composition through time. Diversity at genus level revealed a more stable community structure, with an overwhelming dominance of the square archaeon Haloquadratum in the three metagenomes. Furthermore, functional annotation was carried out in order to detect genes related to metabolic processes, such as carbon, nitrogen, and sulfur cycles. The presence of gene sequences related to nitrogen fixation, ammonia oxidation, sulfate reduction, sulfur oxidation, and phosphate solubilization were detected. Through binning methods, four putative novel genomes were obtained, including a possible novel genus belonging to the Bacteroidetes and possible new species for the genera Natronomonas, Halomicrobium, and Haloquadratum. Using a metagenomic approach, a 3-year study has been performed in a Caribbean hypersaline environment. When compared to other salterns around the world, the Cabo Rojo salterns harbor a similar community composition, which is stable through time. Moreover, an analysis of gene composition highlights the importance of the microbial community in the biogeochemical cycles at hypersaline environments.

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