Soybean microbiome recovery after disruption is modulated by the seed and not the soil microbiome

Endophytic microbiome of healthy seeds forms a symbiotic relationship with their host. Seeds and environment are sources of microbes that colonise the developing plant, however, the influence of each remains unclear. Here, using irradiation combined with surface sterilisation to generate near-axenic seeds with disrupted and reduced microbiome, we contrasted colonisation potential of seed and soil microbiome. We hypothesised that the seed microbiome would be the primary coloniser of the plant endophytic compartments. Our experimental design comprised four treatments, using soybean as a model plant: 1) nearly axenic seeds growing in a sterile environment, 2) non-axenic seeds inoculated with a microbial soil extract, 3) nearly axenic seeds inoculated with a microbial seed extract, and 4) nearly axenic seeds inoculated with a microbial soil extract. After 14 days of growth, plants were harvested, and DNA was extracted from the shoot, roots, rhizosphere, and subjected to 16S rRNA gene amplicon sequencing, qPCR quantification of the total community and functional genes involved in the N-cycle. Community dynamics were similar for most treatments within their respective compartments, except for the soil treatment, where rhizosphere and root microbiome differed from other treatments, suggesting that the soil microbiome colonises the belowground compartment efficiently only when the seed microbiome is severely disrupted. For the shoot, all treatments resembled the seed microbiome treatment, suggesting that the seed-borne bacteria colonise the aboveground compartment preferentially. Our results highlight the primacy of the seed microbiome over the soils during early colonisation, putting seed microbes as potential candidates of microbiome engineering efforts.

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Deconstructing the Soil Microbiome into Reduced-Complexity Functional Modules

mBio ◽

10.1128/mbio.01349-20 ◽

2020 ◽

Vol 11 (4) ◽

Author(s):

Dan Naylor ◽

Sarah Fansler ◽

Colin Brislawn ◽

William C. Nelson ◽

Kirsten S. Hofmockel ◽

...

Keyword(s):

Amplicon Sequencing ◽

Low Complexity ◽

Soil Extract ◽

Soil Microbiome ◽

Functional Modules ◽

Anaerobic Conditions ◽

Metabolic Potential ◽

16S Rrna Amplicon Sequencing ◽

Alternative Approach ◽

Reduced Complexity

ABSTRACT The soil microbiome represents one of the most complex microbial communities on the planet, encompassing thousands of taxa and metabolic pathways, rendering holistic analyses computationally intensive and difficult. Here, we developed an alternative approach in which the complex soil microbiome was broken into components (“functional modules”), based on metabolic capacities, for individual characterization. We hypothesized that reproducible, low-complexity communities that represent functional modules could be obtained through targeted enrichments and that, in combination, they would encompass a large extent of the soil microbiome diversity. Enrichments were performed on a starting soil inoculum with defined media based on specific carbon substrates, antibiotics, alternative electron acceptors under anaerobic conditions, or alternative growing conditions reflective of common field stresses. The resultant communities were evaluated through 16S rRNA amplicon sequencing. Less permissive modules (anaerobic conditions, complex polysaccharides, and certain stresses) resulted in more distinct community profiles with higher richness and more variability between replicates, whereas modules with simple substrates were dominated by fewer species and were more reproducible. Collectively, approximately 27% of unique taxa present in the liquid soil extract control were found across functional modules. Taxa that were underrepresented or undetected in the source soil were also enriched across the modules. Metatranscriptomic analyses were carried out on a subset of the modules to investigate differences in functional gene expression. These results demonstrate that by dissecting the soil microbiome into discrete components it is possible to obtain a more comprehensive view of the soil microbiome and its biochemical potential than would be possible using more holistic analyses. IMPORTANCE The taxonomic and functional diversity inherent to the soil microbiome complicate assessments of the metabolic potential carried out by the community members. An alternative approach is to break down the soil microbiome into reduced-complexity subsets based on metabolic capacities (functional modules) prior to sequencing and analysis. Here, we demonstrate that this approach successfully identified specific phylogenetic and biochemical traits of the soil microbiome that otherwise remained hidden from a more top-down analysis.

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Quantitative insights into effects of intrapartum antibiotics and birth mode on infant gut microbiota in relation to well-being during the first year of life

10.1101/2021.11.01.21265735 ◽

2021 ◽

Author(s):

Katri Korpela ◽

Roosa Jokela ◽

Ching Jian ◽

Evgenia Dikareva ◽

Anne Nikkonen ◽

...

Keyword(s):

Gut Microbiota ◽

Community Dynamics ◽

Gastrointestinal Symptoms ◽

Well Being ◽

Amplicon Sequencing ◽

First Year ◽

Rrna Gene ◽

Absolute Abundance ◽

Abundance Estimates ◽

First Year Of Life

Background and aims Caesarean section (CS)-birth and maternally administered intrapartum antibiotics (IP) affect colonization of the neonate. We compared the effects of CS delivery and IP antibiotics on infant gut microbiota development and wellbeing over the first year. To understand the developing community dynamics, we focused on absolute bacterial abundance estimates over relative abundances. Methods We studied 144 healthy infants born between gestational weeks 37-42 vaginally without antibiotics (N=58), with IP penicillin (N=25) or cephalosporin (N=13), or by CS with IP cephalosporin (N=34) or other antibiotics (N=14). Gut microbiota composition and temporal development was analysed at 5-7 time points during the first year of life using 16S rRNA gene amplicon sequencing, complemented with qPCR to obtain absolute abundance estimates in 92 infants. A mediation analysis was carried out to identify taxa linked to gastrointestinal function and discomfort (crying, defecation frequency and signs of gastrointestinal symptoms) and birth interventions. Results Based on absolute abundance estimates, depletion of Bacteroides spp. was specific to CS birth while decreased bifidobacteria and increased Bacilli were common to CS birth and exposure to IP antibiotics in vaginal delivery. Abundance of numerous taxa differed between the birth modes among cephalosporin-exposed infants. Penicillin had a milder impact on the infant gut microbiota than cephalosporin. The effects of both CS birth and IP antibiotics on infant gut microbiota associated with increased gastrointestinal symptoms during the first months. Conclusion CS birth and maternal IP antibiotics have both specific and overlapping effects on infant gut microbiota development. The resulting microbiota deviations were found to associate with gastrointestinal symptoms in infancy.

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Unlocking a high bacterial diversity in the coralloid root microbiome from the cycad genusDioon

10.1101/381798 ◽

2018 ◽

Cited By ~ 1

Author(s):

Pablo de Jesús Suárez-Moo ◽

Andrew P. Vovides ◽

M. Patrick Griffith ◽

Francisco Barona-Gómez ◽

Angélica Cibrián-Jaramillo

Keyword(s):

Bacterial Diversity ◽

Natural Populations ◽

Amplicon Sequencing ◽

Botanical Garden ◽

Taxonomic Composition ◽

Rrna Gene ◽

Biological Interactions ◽

Plant Growth Promoting ◽

Coralloid Roots ◽

Root Microbiome

AbstractCycads are among the few plants that have developed specialized roots to host nitrogen-fixing bacteria. We describe the bacterial diversity of the coralloid roots from sevenDioonspecies and their surrounding rhizosphere and soil. Using 16S rRNA gene amplicon sequencing, we found that all coralloid roots are inhabited by a broad diversity of bacterial groups, including cyanobacteria and Rhizobiales among the most abundant groups. The diversity and composition of the endophytes are similar in the six Mexican species ofDioonthat we evaluated, suggesting a recent divergence ofDioonpopulations and/or similar plant-driven restrictions in maintaining the coralloid root microbiome. Botanical garden samples and natural populations have a similar taxonomic composition, although the beta diversity differed between these populations. The rhizosphere surrounding the coralloid root serves as a reservoir and source of mostly diazotroph and plant growth-promoting groups that colonize the coralloid endosphere. In the case of cyanobacteria, the endosphere is enriched withNostocspp andCalothrixspp that are closely related to previously reported symbiont genera in cycads and other early divergent plants. The data reported here provide an in-depth taxonomic characterization of the bacterial community associated with coralloid root microbiome. The functional aspects of the endophytes, their biological interactions, and their evolutionary history are the next research step in this recently discovered diversity within the cycad coralloid root microbiome.

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Strengths and Limitations of 16S rRNA Gene Amplicon Sequencing in Revealing Temporal Microbial Community Dynamics

PLoS ONE ◽

10.1371/journal.pone.0093827 ◽

2014 ◽

Vol 9 (4) ◽

pp. e93827 ◽

Cited By ~ 246

Author(s):

Rachel Poretsky ◽

Luis M. Rodriguez-R ◽

Chengwei Luo ◽

Despina Tsementzi ◽

Konstantinos T. Konstantinidis

Keyword(s):

Microbial Community ◽

16S Rrna ◽

16S Rrna Gene ◽

Community Dynamics ◽

Amplicon Sequencing ◽

Rrna Gene ◽

Microbial Community Dynamics

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Wine terroir and the soil microbiome: an amplicon sequencing–based assessment of the Barossa Valley and its sub-regions

10.1101/2020.08.12.246447 ◽

2020 ◽

Author(s):

Jia Zhou ◽

Timothy R. Cavagnaro ◽

Roberta De Bei ◽

Tiffanie M. Nelson ◽

John R. Stephen ◽

...

Keyword(s):

Microbial Communities ◽

Microbial Community Composition ◽

Geographic Distance ◽

Hypervariable Region ◽

Soil Microbial Communities ◽

Amplicon Sequencing ◽

Soil Microbiome ◽

Rrna Gene ◽

Wine Quality ◽

The Impact

AbstractSoil is an important factor that contributes to the uniqueness of a wine produced by vines grown in specific conditions. Recent data shows that the composition, diversity and function of soil microbial communities may play important roles in determining wine quality and indirectly affect its economic value. Here, we evaluated the impact of environmental variables on the soil microbiomes of 22 Barossa Valley vineyard sites based on the 16S rRNA gene hypervariable region 4. In this study, we report that environmental heterogeneity (soil plant-available P content, elevation, rainfall, temperature, spacing between row and spacing between vine) caused more microbial dissimilarity than geographic distance. Vineyards located in cooler and wetter regions showed lower beta diversity and a higher ratio of dominant taxa. Differences in microbial community composition were significantly associated with differences in fruit traits and in wine chemical and metabolomic profiles, highlighting the potential influence of microbial communities on the phenotype of grapevines. Our results suggest that environmental factors affect wine terroir, and this may be mediated by changes in microbial structure, thus providing a basic understanding of how growing conditions affect interactions between plants and their soil microbiomes.

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Fungal and bacterial community dynamics in substrates during the cultivation of morels (Morchella rufobrunnea) indoors

FEMS Microbiology Letters ◽

10.1093/femsle/fnz215 ◽

2019 ◽

Vol 366 (17) ◽

Author(s):

Reid Longley ◽

Gian Maria Niccoló Benucci ◽

Gary Mills ◽

Gregory Bonito

Keyword(s):

Microbial Communities ◽

Internal Transcribed Spacer ◽

Community Dynamics ◽

Amplicon Sequencing ◽

Fungal Communities ◽

Rrna Gene ◽

Prokaryotic Community ◽

Edible Fungi ◽

Microbial Community Dynamics ◽

Bacterial Community Dynamics

ABSTRACT Morel mushrooms (Morchella, Pezizales) are highly prized edible fungi. Approaches to cultivate morels indoors in pasteurized composted substrates have been successful for Morchella rufobrunnea. We used DNA amplicon sequencing of the Internal Transcribed Spacer (ITS) ribosomal DNA and 16S rRNA gene to follow bacterial and fungal communities in substrates during indoor morel cultivation. Our goal was to determine changes in microbial communities at key stages of morel cultivation, which included primordia development, fundament initiation, differentiation and maturation. Additionally, we compared microbial communities between trays that successfully fruited to those that produced conidia and primordia but aborted before ascocarp formation (non-fruiting). The prokaryotic community was dominated by Firmicutes belonging to Bacillus and Paenibacillus with a lower abundance of Flavobacteria. At earlier stages, the fungal community was dominated by Pezizomycetes including Morchella and other species, whereas, later in the cropping cycle Sordariomycetes dominated. Additionally, differences were observed between trays with successful fruiting, which were dominated by Gilmaniella; compared to trays that did not fruit, which were dominated by Cephalotrichum. Our findings inform understanding of microbial community dynamics during morel cultivation, and show that fungal genera, such as Gilmaniella, and prokaryotic genera, such as Bacillus, are abundant in substrates that support M. rufobrunnea fruiting.

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Gut microbiome composition in the Hispanic Community Health Study/Study of Latinos is shaped by geographic relocation, environmental factors, and obesity

Genome Biology ◽

10.1186/s13059-019-1831-z ◽

2019 ◽

Vol 20 (1) ◽

Cited By ~ 14

Author(s):

Robert C. Kaplan ◽

Zheng Wang ◽

Mykhaylo Usyk ◽

Daniela Sotres-Alvarez ◽

Martha L. Daviglus ◽

...

Keyword(s):

Community Health ◽

Gut Microbiome ◽

Alpha Diversity ◽

Amplicon Sequencing ◽

Shannon Index ◽

Health Study ◽

Rrna Gene ◽

Cross Sectional ◽

Hispanic Community ◽

The Usa

Abstract Background Hispanics living in the USA may have unrecognized potential birthplace and lifestyle influences on the gut microbiome. We report a cross-sectional analysis of 1674 participants from four centers of the Hispanic Community Health Study/Study of Latinos (HCHS/SOL), aged 18 to 74 years old at recruitment. Results Amplicon sequencing of 16S rRNA gene V4 and fungal ITS1 fragments from self-collected stool samples indicate that the host microbiome is determined by sociodemographic and migration-related variables. Those who relocate from Latin America to the USA at an early age have reductions in Prevotella to Bacteroides ratios that persist across the life course. Shannon index of alpha diversity in fungi and bacteria is low in those who relocate to the USA in early life. In contrast, those who relocate to the USA during adulthood, over 45 years old, have high bacterial and fungal diversity and high Prevotella to Bacteroides ratios, compared to USA-born and childhood arrivals. Low bacterial diversity is associated in turn with obesity. Contrasting with prior studies, our study of the Latino population shows increasing Prevotella to Bacteroides ratio with greater obesity. Taxa within Acidaminococcus, Megasphaera, Ruminococcaceae, Coriobacteriaceae, Clostridiales, Christensenellaceae, YS2 (Cyanobacteria), and Victivallaceae are significantly associated with both obesity and earlier exposure to the USA, while Oscillospira and Anaerotruncus show paradoxical associations with both obesity and late-life introduction to the USA. Conclusions Our analysis of the gut microbiome of Latinos demonstrates unique features that might be responsible for health disparities affecting Hispanics living in the USA.

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Much ado about nothing? Off-target amplification can lead to false-positive bacterial brain microbiome detection in healthy and Parkinson’s disease individuals

Microbiome ◽

10.1186/s40168-021-01012-1 ◽

2021 ◽

Vol 9 (1) ◽

Author(s):

Janis R. Bedarf ◽

Naiara Beraza ◽

Hassan Khazneh ◽

Ezgi Özkurt ◽

David Baker ◽

...

Keyword(s):

Parkinson’S Disease ◽

16S Rrna ◽

16S Rrna Gene ◽

False Positive ◽

Gene Sequencing ◽

Bacterial Biomass ◽

16S Rrna Gene Sequencing ◽

Amplicon Sequencing ◽

Rrna Gene ◽

Rrna Gene Sequencing

Abstract Background Recent studies suggested the existence of (poly-)microbial infections in human brains. These have been described either as putative pathogens linked to the neuro-inflammatory changes seen in Parkinson’s disease (PD) and Alzheimer’s disease (AD) or as a “brain microbiome” in the context of healthy patients’ brain samples. Methods Using 16S rRNA gene sequencing, we tested the hypothesis that there is a bacterial brain microbiome. We evaluated brain samples from healthy human subjects and individuals suffering from PD (olfactory bulb and pre-frontal cortex), as well as murine brains. In line with state-of-the-art recommendations, we included several negative and positive controls in our analysis and estimated total bacterial biomass by 16S rRNA gene qPCR. Results Amplicon sequencing did detect bacterial signals in both human and murine samples, but estimated bacterial biomass was extremely low in all samples. Stringent reanalyses implied bacterial signals being explained by a combination of exogenous DNA contamination (54.8%) and false positive amplification of host DNA (34.2%, off-target amplicons). Several seemingly brain-enriched microbes in our dataset turned out to be false-positive signals upon closer examination. We identified off-target amplification as a major confounding factor in low-bacterial/high-host-DNA scenarios. These amplified human or mouse DNA sequences were clustered and falsely assigned to bacterial taxa in the majority of tested amplicon sequencing pipelines. Off-target amplicons seemed to be related to the tissue’s sterility and could also be found in independent brain 16S rRNA gene sequences. Conclusions Taxonomic signals obtained from (extremely) low biomass samples by 16S rRNA gene sequencing must be scrutinized closely to exclude the possibility of off-target amplifications, amplicons that can only appear enriched in biological samples, but are sometimes assigned to bacterial taxa. Sequences must be explicitly matched against any possible background genomes present in large quantities (i.e., the host genome). Using close scrutiny in our approach, we find no evidence supporting the hypothetical presence of either a brain microbiome or a bacterial infection in PD brains.

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Retinitis pigmentosa is associated with shifts in the gut microbiome

Scientific Reports ◽

10.1038/s41598-021-86052-1 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Oksana Kutsyr ◽

Lucía Maestre-Carballa ◽

Mónica Lluesma-Gomez ◽

Manuel Martinez-Garcia ◽

Nicolás Cuenca ◽

...

Keyword(s):

Retinitis Pigmentosa ◽

Gut Microbiome ◽

Functional Decline ◽

Retinal Disease ◽

Photoreceptor Cells ◽

Amplicon Sequencing ◽

Rrna Gene ◽

Sequencing Data ◽

Alpha And Beta Diversity ◽

Potential Biomarker

AbstractThe gut microbiome is known to influence the pathogenesis and progression of neurodegenerative diseases. However, there has been relatively little focus upon the implications of the gut microbiome in retinal diseases such as retinitis pigmentosa (RP). Here, we investigated changes in gut microbiome composition linked to RP, by assessing both retinal degeneration and gut microbiome in the rd10 mouse model of RP as compared to control C57BL/6J mice. In rd10 mice, retinal responsiveness to flashlight stimuli and visual acuity were deteriorated with respect to observed in age-matched control mice. This functional decline in dystrophic animals was accompanied by photoreceptor loss, morphologic anomalies in photoreceptor cells and retinal reactive gliosis. Furthermore, 16S rRNA gene amplicon sequencing data showed a microbial gut dysbiosis with differences in alpha and beta diversity at the genera, species and amplicon sequence variants (ASV) levels between dystrophic and control mice. Remarkably, four fairly common ASV in healthy gut microbiome belonging to Rikenella spp., Muribaculaceace spp., Prevotellaceae UCG-001 spp., and Bacilli spp. were absent in the gut microbiome of retinal disease mice, while Bacteroides caecimuris was significantly enriched in mice with RP. The results indicate that retinal degenerative changes in RP are linked to relevant gut microbiome changes. The findings suggest that microbiome shifting could be considered as potential biomarker and therapeutic target for retinal degenerative diseases.

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Oral Microbiota Identifies Patients in Early Onset Rheumatoid Arthritis

Microorganisms ◽

10.3390/microorganisms9081657 ◽

2021 ◽

Vol 9 (8) ◽

pp. 1657

Author(s):

Anders Esberg ◽

Linda Johansson ◽

Ingegerd Johansson ◽

Solbritt Rantapää Dahlqvist

Keyword(s):

Rheumatoid Arthritis ◽

Early Onset ◽

Amplicon Sequencing ◽

Oral Bacteria ◽

Oral Microbiome ◽

Rrna Gene ◽

Oral Microbiota ◽

Disease Manifestation ◽

Periodontal Status ◽

Quality Register

Rheumatoid arthritis (RA) is the most common autoimmune inflammatory disease, and single periodontitis-associated bacteria have been suggested in disease manifestation. Here, the oral microbiota was characterized in relation to the early onset of RA (eRA) taking periodontal status into consideration. 16S rRNA gene amplicon sequencing of saliva bacterial DNA from 61 eRA patients without disease-modifying anti-rheumatic drugs and 59 matched controls was performed. Taxonomic classification at 98.5% was conducted against the Human Oral Microbiome Database, microbiota functions were predicted using PICRUSt, and periodontal status linked from the Swedish quality register for clinically assessed caries and periodontitis. The participants were classified into three distinct microbiota-based cluster groups with cluster allocation differences by eRA status. Independently of periodontal status, eRA patients had enriched levels of Prevotella pleuritidis, Treponema denticola, Porphyromonas endodontalis and Filifactor alocis species and in the Porphyromonas and Fusobacterium genera and functions linked to ornithine metabolism, glucosylceramidase, beta-lactamase resistance, biphenyl degradation, fatty acid metabolism and 17-beta-estradiol-17-dehydrogenase metabolism. The results support a deviating oral microbiota composition already in eRA patients compared with healthy controls and highlight a panel of oral bacteria that may be useful in eRA risk assessment in both periodontally healthy and diseased persons.

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