Symbiont community diversity is more constrained in holobionts that tolerate diverse stressors

AbstractCoral reefs are experiencing global declines as climate change and other stressors cause environmental conditions to exceed the physiological tolerances of host organisms and their microbial symbionts (collectively termed the holobiont). To assess the role of symbiont community composition in holobiont stress tolerance, diversity metrics and abundances of obligate dinoflagellate endosymbionts (Family: Symbiodiniaceae) were quantified from eight Acropora millepora coral colonies (hereafter called genets) that thrived under or responded poorly to various stressors. Four ‘best performer’ coral genets were selected for analysis because they survived 10 days of high temperature, high pCO2, bacterial addition, or combined stressors, whereas four ‘worst performer’ coral genets were analyzed because they experienced significant mortality under these stressors. At the end of the experimental period, seven of eight coral genets mainly hosted Cladocopium symbionts, but also contained Brevolium, Durusdinium, and/or Gerakladinium symbionts at lower abundances (<0.1% of the total community). After 10 days of stress, symbiont communities varied significantly among host genets, but not stress treatments, based on alpha and beta diversity metrics. A generalized joint attribute model (GJAM) also predicted that symbiont communities were primarily sensitive to host genet at regional scales. Indicator species analysis and the regional GJAM model identified significant associations among particular symbionts and host genet performance. Specifically, Cladocopium 3k contributed to the success of best performer host genets under various stressful conditions, whereas Durusdinium glynnii and Durusdinium trenchii were significantly associated with one worst performer genet. Cladocopium 3k dominance should be more broadly investigated as a potential predictor of stress resistance in Acropora millepora populations across their geographic range. Symbiodiniaceae communities exhibited higher richness and variance (beta diversity) in the worst performing genets. These findings highlight that symbiont community diversity metrics may be important indicators of resilience in hosts central to diverse disciplines, from agriculture to medicine.

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The power of microbiome studies: some considerations on which alpha and beta metrics to use and how to report analysis the results

10.21203/rs.3.rs-698991/v1 ◽

2021 ◽

Author(s):

Jannigje Gerdien Kers ◽

Edoardo Saccenti

Keyword(s):

Sample Size ◽

Beta Diversity ◽

Sequence Data ◽

Animal Experiments ◽

Simulated Data ◽

Alpha Diversity ◽

Data Sets ◽

Power Calculations ◽

Alpha And Beta Diversity ◽

Diversity Metrics

Abstract Since sequencing techniques become less expensive, larger sample sizes are applicable for microbiota studies. The aim of this study is to show how, and to what extent, different diversity metrics and different compositions of the microbiota influence the needed sample size to observed dissimilar groups. Empirical 16S rRNA amplicon sequence data obtained from animal experiments, observational human data, and simulated data was used to perform retrospective power calculations. A wide variation of alpha diversity and beta diversity metrics were used to compare the different microbiota data sets and the effect on the sample size. Our data showed that beta diversity metrics are most sensitive to observe differences compared to alpha diversity metrics. The structure of the data influenced which alpha metrics are most sensitive. Regarding beta diversity, the Bray-Curtis metric is in general most sensitive to observe differences between groups, resulting in lower sample size and potential publication bias. We recommend to perform power calculations and to use multiple diversity metrics as an outcome measure. To improve microbiota studies awareness needs to be raised on the sensitivity and bias for microbiota research outcomes created by the used metrics rather than biological differences. We have seen that different alpha and beta diversity metrics lead to different study power: on the basis of this observation, one could be naturally tempted to try all possible metrics until one or more are found that give a statistically significant test result, i.e. p-value < α. This way of proceeding is one of the many forms of the so-called p-value hacking. To this end, in our opinion, the only way to protect ourselves from (the temptation of) p-hacking would be to publish, and we stress here the word publish, a statistical plan before experiments are initiated: this practice is customary for clinical trials where a statistical plan describing the endpoints and the corresponding statistical analyses must be disclosed before the start of the study.

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Inconsistent Patterns of Microbial Diversity and Composition Between Highly Similar Sequencing Protocols: A Case Study With Reef-Building Corals

Frontiers in Microbiology ◽

10.3389/fmicb.2021.740932 ◽

2021 ◽

Vol 12 ◽

Author(s):

Hannah E. Epstein ◽

Alejandra Hernandez-Agreda ◽

Samuel Starko ◽

Julia K. Baum ◽

Rebecca Vega Thurber

Keyword(s):

16S Rrna ◽

16S Rrna Gene ◽

Beta Diversity ◽

Sequence Data ◽

Alpha Diversity ◽

Gene Profiling ◽

Rrna Gene ◽

Sequencing Platform ◽

Alpha And Beta Diversity ◽

Diversity Metrics

16S rRNA gene profiling (amplicon sequencing) is a popular technique for understanding host-associated and environmental microbial communities. Most protocols for sequencing amplicon libraries follow a standardized pipeline that can differ slightly depending on laboratory facility and user. Given that the same variable region of the 16S gene is targeted, it is generally accepted that sequencing output from differing protocols are comparable and this assumption underlies our ability to identify universal patterns in microbial dynamics through meta-analyses. However, discrepant results from a combined 16S rRNA gene dataset prepared by two labs whose protocols differed only in DNA polymerase and sequencing platform led us to scrutinize the outputs and challenge the idea of confidently combining them for standard microbiome analysis. Using technical replicates of reef-building coral samples from two species, Montipora aequituberculata and Porites lobata, we evaluated the consistency of alpha and beta diversity metrics between data resulting from these highly similar protocols. While we found minimal variation in alpha diversity between platform, significant differences were revealed with most beta diversity metrics, dependent on host species. These inconsistencies persisted following removal of low abundance taxa and when comparing across higher taxonomic levels, suggesting that bacterial community differences associated with sequencing protocol are likely to be context dependent and difficult to correct without extensive validation work. The results of this study encourage caution in the statistical comparison and interpretation of studies that combine rRNA gene sequence data from distinct protocols and point to a need for further work identifying mechanistic causes of these observed differences.

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Microbiological description of self-overgrowing spoil heaps and sand quarries in Nordwest Russia

10.5194/egusphere-egu21-2086 ◽

2021 ◽

Author(s):

Aleksei Zverev ◽

Anastasiia Kimeklis ◽

Grigory Gladkov ◽

Arina Kichko ◽

Evgeny Andronov ◽

...

Keyword(s):

Beta Diversity ◽

Alpha Diversity ◽

Illumina Miseq ◽

Differential Abundance ◽

Alpha And Beta Diversity ◽

Technogenic Landscapes ◽

Different Types ◽

Undisturbed Soils ◽

Disturbed Soils ◽

Diversity Metrics

Self-overgrowing recovery of disturbed soils is one of important processes in reclamation of disturbed soils. Different types of anthropogenic disturbances followed by variety of soil types and their genesis leads to different bacterial communities, envolved in reclamation processes. Here we describe regional self-overgrowing soils in two location (Novgorod region, Northwest Russia). We analyse top level of industrial disturbed soils after coil mining (spoil tips with extremely low pH, and overburden soil) and sand quarry dumps followed by local undisturbed soils.We perform 16s amplicone sequencind (v4-region) by Illumina MiSEQ and chemical routine analysis (pH, C, N and other). We provide alpha- and beta-diversity analysis, followed by CCA and analysis of differential abundance of taxa.Sand quarry dumps and regional soils looks common on phyla level, and represent common soil phyla like Proteobacteria, Actinobacteria and Verrucomicrobia. Alpha-diversity metrics aslo are similar, despite difference in beta-diversity. Overburden soil and soil from spot tips, by contrast, is very different even in phylum level. Main intermediants here are Actinobacteria, Chloroflexi &#1080; Nitrospirae. Also they show extremely low alpha-diversity metrics.This work was supported by RSF 17-16-01030, &#171;Dynamics of soil biota in chronoseries of post-technogenic landscapes: analysis of soil-ecological efficiency of ecosystem restoration processes&#187;

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Alpha and beta diversity of birds along elevational vegetation zones on the southern slope of Altai Mountains: Implication for conservation

Global Ecology and Conservation ◽

10.1016/j.gecco.2019.e00643 ◽

2019 ◽

Vol 19 ◽

pp. e00643 ◽

Cited By ~ 1

Author(s):

Na Li ◽

Hongjun Chu ◽

Yingjie Qi ◽

Chunwang Li ◽

Xiaoge Ping ◽

...

Keyword(s):

Beta Diversity ◽

Altai Mountains ◽

Southern Slope ◽

Alpha And Beta Diversity ◽

Vegetation Zones

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Site‐specific impacts of a major hurricane on alpha and beta diversity in tropical forest seedling communities

Ecosphere ◽

10.1002/ecs2.3651 ◽

2021 ◽

Vol 12 (7) ◽

Author(s):

Samantha J. Worthy ◽

Vanessa E. Rubio ◽

Kirstin Staiger ◽

Boris Ngouajio ◽

Jie Yang ◽

...

Keyword(s):

Tropical Forest ◽

Beta Diversity ◽

Site Specific ◽

Alpha And Beta Diversity ◽

Major Hurricane

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Effect of Bovine MFGM and LF in Infant Formula on Gut Microbiome and Metabolome at Four Months of Age

Current Developments in Nutrition ◽

10.1093/cdn/nzab027 ◽

2021 ◽

Author(s):

Maciej Chichlowski ◽

Nicholas Bokulich ◽

Cheryl L Harris ◽

Jennifer L Wampler ◽

Fei Li ◽

...

Keyword(s):

Infant Formula ◽

Beta Diversity ◽

Milk Fat ◽

Alpha Diversity ◽

Illumina Miseq ◽

Rrna Gene ◽

Term Infants ◽

Linear Discriminant ◽

Alpha And Beta Diversity ◽

Metabolite Profiles

Abstract Background Milk fat globule membrane (MFGM) and lactoferrin (LF) are human milk bioactive components demonstrated to support gastrointestinal (GI) and immune development. Significantly fewer diarrhea and respiratory-associated adverse events through 18 months of age were previously reported in healthy term infants fed a cow's milk-based infant formula with added source of bovine MFGM and bovine LF through 12 months of age. Objectives To compare microbiota and metabolite profiles in a subset of study participants. Methods Stool samples were collected at Baseline (10–14 days of age) and Day 120 (MFGM + LF: 26, Control: 33). Bacterial community profiling was performed via16S rRNA gene sequencing (Illumina MiSeq) and alpha and beta diversity were analyzed (QIIME 2). Differentially abundant taxa were determined using Linear discriminant analysis effect size (LefSE) and visualized (Metacoder). Untargeted stool metabolites were analyzed (HPLC/mass spectroscopy) and expressed as the fold-change between group means (Control: MFGM + LF ratio). Results Alpha diversity increased significantly in both groups from baseline to 4 months. Subtle group differences in beta diversity were demonstrated at 4 months (Jaccard distance; R2 = 0.01, P = 0.042). Specifically, Bacteroides uniformis and Bacteroides plebeius were more abundant in the MFGM + LF group at 4 months. Metabolite profile differences for MFGM + LF vs Control included: lower fecal medium chain fatty acids, deoxycarnitine, and glycochenodeoxycholate, and some higher fecal carbohydrates and steroids (P < 0.05). After applying multiple test correction, the differences in stool metabolomics were not significant. Conclusions Addition of bovine MFGM and LF in infant formula was associated with subtle differences in stool microbiome and metabolome by four months of age, including increased prevalence of Bacteroides species. Stool metabolite profiles may be consistent with altered microbial metabolism. Trial registration: https://clinicaltrials.gov/ct2/show/NCT02274883).

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The Fecal Bacterial Microbiota in Horses with Equine Recurrent Uveitis

Animals ◽

10.3390/ani11030745 ◽

2021 ◽

Vol 11 (3) ◽

pp. 745

Author(s):

Michelle Martin de Bustamante ◽

Diego Gomez ◽

Jennifer MacNicol ◽

Ralph Hamor ◽

Caryn Plummer

Keyword(s):

Beta Diversity ◽

High Throughput Sequencing ◽

Illumina Miseq ◽

Diversity Indices ◽

Rrna Gene ◽

Linear Discriminant ◽

Alpha And Beta Diversity ◽

Bacterial Microbiota ◽

Healthy Control ◽

Equine Recurrent Uveitis

The objective of this study was to describe and compare the fecal bacterial microbiota of horses with equine recurrent uveitis (ERU) and healthy horses using next-generation sequencing techniques. Fecal samples were collected from 15 client-owned horses previously diagnosed with ERU on complete ophthalmic examination. For each fecal sample obtained from a horse with ERU, a sample was collected from an environmentally matched healthy control with no evidence of ocular disease. The Illumina MiSeq sequencer was used for high-throughput sequencing of the V4 region of the 16S rRNA gene. The relative abundance of predominant taxa, and alpha and beta diversity indices were calculated and compared between groups. The phyla Firmicutes, Bacteroidetes, Verrucomicrobia, and Proteobacteria predominated in both ERU and control horses, accounting for greater than 60% of sequences. Based on linear discriminant analysis effect size (LEfSe), no taxa were found to be enriched in either group. No significant differences were observed in alpha and beta diversity indices between groups (p > 0.05 for all tests). Equine recurrent uveitis is not associated with alteration of the gastrointestinal bacterial microbiota when compared with healthy controls.

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Partitioning tree diversity patterns to prioritize conservation investments

Environmental Conservation ◽

10.1017/s0376892921000060 ◽

2021 ◽

pp. 1-9

Author(s):

Patrick F McKenzie ◽

Gwenllian D Iacona ◽

Eric R Larson ◽

Paul R Armsworth

Keyword(s):

Protected Areas ◽

Predictive Models ◽

Tree Species ◽

Beta Diversity ◽

Distribution Data ◽

Gamma Diversity ◽

Conservation Practice ◽

Alpha And Beta Diversity ◽

Community Turnover ◽

Data Limitations

Summary The available tools and approaches to inform conservation decisions commonly assume detailed distribution data. We examine how well-established ecological concepts about patterns in local richness and community turnover can help overcome data limitations when planning future protected areas. To inform our analyses, we surveyed tree species in protected areas in the southern Appalachian Mountains in the eastern USA. We used the survey data to construct predictive models for alpha and beta diversity based on readily observed biophysical variables and combined them to create a heuristic that could predict among-site richness in trees (gamma diversity). The predictive models suggest that site elevation and latitude in this montane system explain much of the variation in alpha and beta diversity in tree species. We tested how well resulting protected areas would represent species if a conservation planner lacking detailed species inventories for candidate sites were to rely only on our alpha, beta and gamma diversity predictions. Our approach selected sites that, when aggregated, covered a large proportion of the overall species pool. The combined gamma diversity models performed even better when we also accounted for the cost of protecting sites. Our results demonstrate that classic community biogeography concepts remain highly relevant to conservation practice today.

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Gut Microbiome in Psoriasis: An Updated Review

Pathogens ◽

10.3390/pathogens9060463 ◽

2020 ◽

Vol 9 (6) ◽

pp. 463

Author(s):

Mariusz Sikora ◽

Albert Stec ◽

Magdalena Chrabaszcz ◽

Aleksandra Knot ◽

Anna Waskiel-Burnat ◽

...

Keyword(s):

Gut Microbiome ◽

Beta Diversity ◽

Large Scale ◽

Skin Diseases ◽

Intestinal Barrier ◽

Alpha Diversity ◽

Current Data ◽

Intestinal Microbiome ◽

Microbial Composition ◽

Alpha And Beta Diversity

(1) Background: A growing body of evidence highlights that intestinal dysbiosis is associated with the development of psoriasis. The gut–skin axis is the novel concept of the interaction between skin diseases and microbiome through inflammatory mediators, metabolites and the intestinal barrier. The objective of this study was to synthesize current data on the gut microbial composition in psoriasis. (2) Methods: We conducted a systematic review of studies investigating intestinal microbiome in psoriasis, using the PRISMA checklist. We searched MEDLINE, EMBASE, and Web of Science databases for relevant published articles (2000–2020). (3) Results: All of the 10 retrieved studies reported alterations in the gut microbiome in patients with psoriasis. Eight studies assessed alpha- and beta-diversity. Four of them reported a lack of change in alpha-diversity, but all confirmed significant changes in beta-diversity. At the phylum-level, at least two or more studies reported a lower relative abundance of Bacteroidetes, and higher Firmicutes in psoriasis patients versus healthy controls. (4) Conclusions: There is a significant association between alterations in gut microbial composition and psoriasis; however, there is high heterogeneity between studies. More unified methodological standards in large-scale studies are needed to understand microbiota’s contribution to psoriasis pathogenesis and its modulation as a potential therapeutic strategy.

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