Application of a High-Throughput Amplicon Sequencing Method to Chart the Bacterial Communities that Are Associated with European Fermented Meats from Different Origins

Insight into the microbial species diversity of fermented meats is not only paramount to gain control over quality development, but also to better understand the link with processing technology and geographical origin. To study the composition of the microbial communities, the use of culture-independent methods is increasingly popular but often still suffers from drawbacks, such as a limited taxonomic resolution. This study aimed to apply a previously developed high-throughput amplicon sequencing (HTS) method targeting the 16S rRNA and tuf genes to characterize the bacterial communities in European fermented meats in greater detail. The data obtained broadened the view on the microbial communities that were associated with the various products examined, revealing the presence of previously underreported subdominant species. Moreover, the composition of these communities could be linked to the specificities of individual products, in particular pH, salt content, and geographical origin. In contrast, no clear links were found between the volatile organic compound profiles of the different products and the country of origin, distinct processing conditions, or microbial communities. Future application of the HTS method offers the potential to further unravel complex microbial communities in fermented meats, as well as to assess the impact of different processing conditions on microbial consortia.

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Extremely Halophilic Biohydrogen Producing Microbial Communities from High-Salinity Soil and Salt Evaporation Pond

Fuels ◽

10.3390/fuels2020014 ◽

2021 ◽

Vol 2 (2) ◽

pp. 241-252

Author(s):

Dyah Asri Handayani Taroepratjeka ◽

Tsuyoshi Imai ◽

Prapaipid Chairattanamanokorn ◽

Alissara Reungsang

Keyword(s):

Microbial Communities ◽

High Throughput ◽

High Throughput Sequencing ◽

High Salinity ◽

Amplicon Sequencing ◽

Spatial Proximity ◽

Lignocellulosic Waste ◽

Evaporation Pond ◽

Operational Taxonomic Units ◽

Determining Factor

Extreme halophiles offer the advantage to save on the costs of sterilization and water for biohydrogen production from lignocellulosic waste after the pretreatment process with their ability to withstand extreme salt concentrations. This study identifies the dominant hydrogen-producing genera and species among the acclimatized, extremely halotolerant microbial communities taken from two salt-damaged soil locations in Khon Kaen and one location from the salt evaporation pond in Samut Sakhon, Thailand. The microbial communities’ V3–V4 regions of 16srRNA were analyzed using high-throughput amplicon sequencing. A total of 345 operational taxonomic units were obtained and the high-throughput sequencing confirmed that Firmicutes was the dominant phyla of the three communities. Halanaerobium fermentans and Halanaerobacter lacunarum were the dominant hydrogen-producing species of the communities. Spatial proximity was not found to be a determining factor for similarities between these extremely halophilic microbial communities. Through the study of the microbial communities, strategies can be developed to increase biohydrogen molar yield.

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Shaping of the Present-Day Deep Biosphere at Chicxulub by the Impact Catastrophe That Ended the Cretaceous

Frontiers in Microbiology ◽

10.3389/fmicb.2021.668240 ◽

2021 ◽

Vol 12 ◽

Author(s):

Charles S. Cockell ◽

Bettina Schaefer ◽

Cornelia Wuchter ◽

Marco J. L. Coolen ◽

Kliti Grice ◽

...

Keyword(s):

Microbial Communities ◽

Amplicon Sequencing ◽

Granitic Rocks ◽

Rrna Gene ◽

Deep Biosphere ◽

Deep Subsurface ◽

Cell Biomass ◽

Colonization Potential ◽

The Impact

We report on the effect of the end-Cretaceous impact event on the present-day deep microbial biosphere at the impact site. IODP-ICDP Expedition 364 drilled into the peak ring of the Chicxulub crater, México, allowing us to investigate the microbial communities within this structure. Increased cell biomass was found in the impact suevite, which was deposited within the first few hours of the Cenozoic, demonstrating that the impact produced a new lithological horizon that caused a long-term improvement in deep subsurface colonization potential. In the biologically impoverished granitic rocks, we observed increased cell abundances at impact-induced geological interfaces, that can be attributed to the nutritionally diverse substrates and/or elevated fluid flow. 16S rRNA gene amplicon sequencing revealed taxonomically distinct microbial communities in each crater lithology. These observations show that the impact caused geological deformation that continues to shape the deep subsurface biosphere at Chicxulub in the present day.

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Hill-based Dissimilarity Indices and Null Models for Analysis of Microbial Community Assembly

10.21203/rs.3.rs-33130/v1 ◽

2020 ◽

Author(s):

Oskar Modin ◽

Raquel Liebana ◽

Soroush Saheb-Alam ◽

Britt-Marie Wilén ◽

Carolina Suarez ◽

...

Keyword(s):

Microbial Community ◽

Microbial Communities ◽

Community Assembly ◽

Null Model ◽

Amplicon Sequencing ◽

Null Models ◽

Marker Genes ◽

Experimental Systems ◽

Microbial Community Assembly ◽

The Impact

Abstract Background: High-throughput amplicon sequencing of marker genes, such as the 16S rRNA gene in Bacteria and Archaea, provides a wealth of information about the composition of microbial communities. To quantify differences between samples and draw conclusions about factors affecting community assembly, dissimilarity indices are typically used. However, results are subject to several biases and data interpretation can be challenging. The Jaccard and Bray-Curtis indices, which are often used to quantify taxonomic dissimilarity, are not necessarily the most logical choices. Instead, we argue that Hill-based indices, which make it possible to systematically investigate the impact of relative abundance on dissimilarity, should be used for robust analysis of data. In combination with a null model, mechanisms of microbial community assembly can be analyzed. Here, we also introduce a new software, qdiv, which enables rapid calculations of Hill-based dissimilarity indices in combination with null models.Results: Using amplicon sequencing data from two experimental systems, aerobic granular sludge (AGS) reactors and microbial fuel cells (MFC), we show that the choice of dissimilarity index can have considerable impact on results and conclusions. High dissimilarity between replicates because of random sampling effects make incidence-based indices less suited for identifying differences between groups of samples. Determining a consensus table based on count tables generated with different bioinformatic pipelines reduced the number of low-abundant, potentially spurious amplicon sequence variants (ASVs) in the data sets, which led to lower dissimilarity between replicates. Analysis with a combination of Hill-based indices and a null model allowed us to show that different ecological mechanisms acted on different fractions of the microbial communities in the experimental systems.Conclusions: Hill-based indices provide a rational framework for analysis of dissimilarity between microbial community samples. In combination with a null model, the effects of deterministic and stochastic community assembly factors on taxa of different relative abundances can be systematically investigated. Calculations of Hill-based dissimilarity indices in combination with a null model can be done in qdiv, which is freely available as a Python package (https://github.com/omvatten/qdiv). In qdiv, a consensus table can also be determined from several count tables generated with different bioinformatic pipelines.

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Deciphering the Influence of Multiple Anthropogenic Inputs on Taxonomic and Functional Profiles of the Microbial Communities in Yitong River, Northeast China

10.21203/rs.3.rs-729563/v1 ◽

2021 ◽

Author(s):

Ying Zhang ◽

Yang Huo ◽

Zhiruo Zhang ◽

Suiyi Zhu ◽

Wei Fan ◽

...

Keyword(s):

Microbial Communities ◽

Northeast China ◽

Environmental Changes ◽

Quantitative Polymerase Chain Reaction ◽

Amplicon Sequencing ◽

Fecal Indicator ◽

16S Rrna Amplicon Sequencing ◽

Anthropogenic Inputs ◽

Wwtp Effluent ◽

The Impact

Abstract We conducted physicochemical parameters analysis, 16S rRNA amplicon sequencing and real-time quantitative polymerase chain reaction to explore the impact of human inputs on the bacterioplankton communities within a tributary of the largest river flowing through a megacity in northeast China. Agriculture largely accounted for the alteration of diversity and functions of the microbial communities. Furthermore, nutrients were significantly declined at the reservoir outlet, and WWTP effluent discharge caused changes in the river microbial community. NH3-N and NO3--N were the main environmental factors that drive the shift of the bacteria community, and rare taxa played a more important role in the response to environmental changes compared with the abundant ones. The occurrence of the human-specific fecal indicator was mostly derived from agriculture, and its increase in relative abundance was observed in the effluent. Thus, our study provides guidance for ecological assessment and management of rivers by revealing the response pattern of river bacterioplankton to multiple types of anthropogenic stressors.

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Dietary and Developmental Shifts in Butterfly-Associated Bacterial Communities

10.1101/196816 ◽

2017 ◽

Author(s):

Kruttika Phalnikar ◽

Krushnamegh Kunte ◽

Deepa Agashe

Keyword(s):

Bacterial Communities ◽

Bacterial Community Composition ◽

Amplicon Sequencing ◽

Butterfly Species ◽

Species Identity ◽

Active Selection ◽

Key Factor ◽

Host Diet ◽

Taxonomic Groups ◽

The Impact

ABSTRACTBacterial communities associated with insects can substantially influence host ecology, evolution and behavior. Host diet is a key factor that shapes bacterial communities, but the impact of dietary transitions across insect development is poorly understood. We analyzed bacterial communities of 12 butterfly species across different development stages, using 16S rDNA amplicon sequencing. Butterfly larvae typically consume leaves of a single host plant, whereas adults are more generalist nectar feeders. Thus, we expected bacterial communities to vary substantially across butterfly development. Surprisingly, very few species showed significant developmental transitions in bacterial communities, suggesting weak impacts of dietary transitions across butterfly development. On the other hand, bacterial communities were strongly influenced by butterfly species identity and dietary variation across species. Larvae of most butterfly species largely mirrored bacterial community composition of their diets, suggesting passive acquisition rather than active selection. Overall, our results suggest that although butterflies harbor distinct microbiomes across taxonomic groups and dietary guilds, the dramatic dietary shifts that occur during development do not impose strong selection to maintain distinct bacterial communities.

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Depth and location influence prokaryotic and eukaryotic microbial community structure in New Zealand fjords

10.1101/680694 ◽

2019 ◽

Author(s):

Sven P. Tobias-Hünefeldt ◽

Stephen R. Wing ◽

Nadjejda Espinel-Velasco ◽

Federico Baltar ◽

Sergio E. Morales

Keyword(s):

Community Structure ◽

New Zealand ◽

Microbial Communities ◽

National Park ◽

Amplicon Sequencing ◽

Forested Catchments ◽

Environmental Forcing ◽

Low Salinity ◽

The Impact ◽

Depth View

SummarySystems with strong horizontal and vertical gradients, such as fjords, are useful models for studying environmental forcing. Here we examine microbial (prokaryotic and eukaryotic) community changes associated with the surface low salinity layer (LSL) and underlying seawater in multiple fjords in Fiordland National Park (New Zealand). High rainfall (1200-8000 mm annually) and linked runoff from native forested catchments results in surface LSLs with high tannin concentrations within each fjord. These gradients are expected to drive changes in microbial communities. We used amplicon sequencing (16S and 18S) to assess the impact of these gradients on microbial communities and identified depth linked changes in diversity and community structure. With increasing depth we observed significant increases in Proteobacteria (15%) and SAR (37%), decreases in Opisthokonta (35%), and transiently increased Bacteroidetes (3% increase from 0 to 40 m, decreasing by 8% at 200 m). Community structure differences were observed along a transect from inner to outer regions, specifically 25% mean relative abundance decreases in Opisthokonta and Bacteroidetes, and increases in SAR (25%) and Proteobacteria (>5%) at the surface, indicating changes based on distance from the ocean. This provides the first in-depth view into the ecological drivers of microbial communities within New Zealand fjords.

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Localization of bacterial communities within gut compartments across Cephalotes turtle ants

Applied and Environmental Microbiology ◽

10.1128/aem.02803-20 ◽

2021 ◽

Author(s):

Peter J. Flynn ◽

Catherine L. D’Amelio ◽

Jon G. Sanders ◽

Jacob A. Russell ◽

Corrie S. Moreau

Keyword(s):

Microbial Community ◽

Microbial Communities ◽

Digestive Tract ◽

Bacterial Communities ◽

Evolutionary History ◽

Amplicon Sequencing ◽

Caste Differentiation ◽

Animal Group ◽

16S Rrna Amplicon Sequencing ◽

Host Phylogeny

Microbial communities within the animal digestive tract often provide important functions for their hosts. The composition of eukaryotes' gut bacteria can be shaped by host diet, vertical bacterial transmission, and physiological variation within the digestive tract. In several ant taxa, recent findings have demonstrated that nitrogen provisioning by symbiotic bacteria makes up for deficiencies in herbivorous diets. Using 16S rRNA amplicon sequencing and qPCR, this study examined bacterial communities at a fine scale across one such animal group, the turtle ant genus Cephalotes. We analyzed the composition and colonization density across four portions of the digestive tract to understand how bacterial diversity is structured across gut compartments, potentially allowing for specific metabolic functions of benefit to the host. In addition, we aimed to understand if caste differentiation or host relatedness influences the gut bacterial communities of Cephalotes ants. Microbial communities were found to vary strongly across Cephalotes gut compartments in ways that transcend both caste and host phylogeny. Despite this, caste and host phylogeny still have detectable effects. We demonstrated microbial community divergence across gut compartments, possibly due to the varying function of each gut compartment for digestion. IMPORTANCE Gut compartments play an important role in structuring the microbial community within individual ants. The gut chambers of the turtle ant digestive tract differ remarkably in symbiont abundance and diversity. Furthermore, caste type explains some variation in the microbiome composition. Finally, the evolutionary history of the Cephalotes species structures the microbiome in our study, which elucidates a trend in which related ants maintain related microbiomes, conceivably owing to co-speciation. Amazingly, gut compartment-specific signatures of microbial diversity, relative abundance, composition, and abundance have been conserved over Cephalotes evolutionary history, signifying that this symbiosis has been largely stable for over 50 million years.

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Taxon appearance from extraction and amplification steps demonstrates the value of multiple controls in tick microbiota analysis

10.1101/714030 ◽

2019 ◽

Cited By ~ 2

Author(s):

Emilie Lejal ◽

Agustín Estrada-Peña ◽

Maud Marsot ◽

Jean-François Cosson ◽

Olivier Rué ◽

...

Keyword(s):

Microbial Communities ◽

Dna Extraction ◽

High Throughput ◽

High Throughput Sequencing ◽

Dna Amplification ◽

Community Diversity ◽

Analytical Process ◽

Sequencing Technologies ◽

And Gender ◽

The Impact

AbstractBackgroundThe development of high throughput sequencing technologies has substantially improved analysis of bacterial community diversity, composition, and functions. Over the last decade, high throughput sequencing has been used extensively to identify the diversity and composition of tick microbial communities. However, a growing number of studies are warning about the impact of contamination brought along the different steps of the analytical process, from DNA extraction to amplification. In low biomass samples, e.g. individual tick samples, these contaminants may represent a large part of the obtained sequences, and thus generate considerable errors in downstream analyses and in the interpretation of results. Most studies of tick microbiota either do not mention the inclusion of controls during the DNA extraction or amplification steps, or consider the lack of an electrophoresis signal as an absence of contamination. In this context, we aimed to assess the proportion of contaminant sequences resulting from these steps. We analyzed the microbiota of individual Ixodes ricinus ticks by including several categories of controls throughout the analytical process: crushing, DNA extraction, and DNA amplification.ResultsControls yielded a significant number of sequences (1,126 to 13,198 mean sequences, depending on the control category). Some operational taxonomic units (OTUs) detected in these controls belong to genera reported in previous tick microbiota studies. In this study, these OTUs accounted for 50.9% of the total number of sequences in our samples, and were considered contaminants. Contamination levels (i.e. the percentage of sequences belonging to OTUs identified as contaminants) varied with tick stage and gender: 76.3% of nymphs and 75% of males demonstrated contamination over 50%, while most females (65.7%) had rates lower than 20%. Contamination mainly corresponded to OTUs detected in crushing and DNA extraction controls, highlighting the importance of carefully controlling these steps.ConclusionHere, we showed that contaminant OTUs from extraction and amplification steps can represent more than half the total sequence yield in sequencing runs, and lead to unreliable results when characterizing tick microbial communities. We thus strongly advise the routine use of negative controls in tick microbiota studies, and more generally in studies involving low biomass samples.

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Diversity and dynamics of microbial communities in brown planthopper at different developmental stages revealed by high‐throughput amplicon sequencing

Insect Science ◽

10.1111/1744-7917.12729 ◽

2019 ◽

Vol 27 (5) ◽

pp. 883-894 ◽

Cited By ~ 1

Author(s):

Zheng‐Liang Wang ◽

Tian‐Zhao Wang ◽

Hang‐Feng Zhu ◽

Hai‐Bo Pan ◽

Xiao‐Ping Yu

Keyword(s):

Microbial Communities ◽

High Throughput ◽

Developmental Stages ◽

Brown Planthopper ◽

Amplicon Sequencing

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Rhizosphere Microbial Community Structure in Relation to Root Location and Plant Iron Nutritional Status

Applied and Environmental Microbiology ◽

10.1128/aem.66.1.345-351.2000 ◽

2000 ◽

Vol 66 (1) ◽

pp. 345-351 ◽

Cited By ~ 347

Author(s):

Ching-Hong Yang ◽

David E. Crowley

Keyword(s):

Community Structure ◽

Nutritional Status ◽

Microbial Communities ◽

16S Rdna ◽

Bacterial Communities ◽

Root Exudate ◽

Primary Root ◽

Root Tips ◽

Root Zones ◽

The Impact

ABSTRACT Root exudate composition and quantity vary in relation to plant nutritional status, but the impact of the differences on rhizosphere microbial communities is not known. To examine this question, we performed an experiment with barley (Hordeum vulgare) plants under iron-limiting and iron-sufficient growth conditions. Plants were grown in an iron-limiting soil in root box microcosms. One-half of the plants were treated with foliar iron every day to inhibit phytosiderophore production and to alter root exudate composition. After 30 days, the bacterial communities associated with different root zones, including the primary root tips, nonelongating secondary root tips, sites of lateral root emergence, and older roots distal from the tip, were characterized by using 16S ribosomal DNA (rDNA) fingerprints generated by PCR-denaturing gradient gel electrophoresis (DGGE). Our results showed that the microbial communities associated with the different root locations produced many common 16S rDNA bands but that the communities could be distinguished by using correspondence analysis. Approximately 40% of the variation between communities could be attributed to plant iron nutritional status. A sequence analysis of clones generated from a single 16S rDNA band obtained at all of the root locations revealed that there were taxonomically different species in the same band, suggesting that the resolving power of DGGE for characterization of community structure at the species level is limited. Our results suggest that the bacterial communities in the rhizosphere are substantially different in different root zones and that a rhizosphere community may be altered by changes in root exudate composition caused by changes in plant iron nutritional status.

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