From reads to operational taxonomic units: an ensemble processing pipeline for MiSeq amplicon sequencing data

Mohamed Mysara; Mercy Njima; Natalie Leys; Jeroen Raes; Pieter Monsieurs

doi:10.1093/gigascience/giw017

Diversity of deep-water coral-associated bacteria and comparison across depth gradients

FEMS Microbiology Ecology ◽

10.1093/femsec/fiz091 ◽

2019 ◽

Vol 95 (7) ◽

Cited By ~ 3

Author(s):

Sigmund Jensen ◽

Martin Hovland ◽

Michael D J Lynch ◽

David G Bourne

Keyword(s):

Deep Water ◽

Amplicon Sequencing ◽

Rrna Gene ◽

Lophelia Pertusa ◽

Sequencing Data ◽

Operational Taxonomic Units ◽

Class Level ◽

Paragorgia Arborea ◽

Depth Gradients ◽

Water Coral

ABSTRACTEnvironmental conditions influence species composition, including the microbial communities that associate with benthic organisms such as corals. In this study we identified and compared bacteria that associate with three common deep-water corals, Lophelia pertusa, Madrepora oculata and Paragorgia arborea, from a reef habitat on the mid-Norwegian shelf. The 16S rRNA gene amplicon sequencing data obtained revealed that >50% of sequences were represented by only five operational taxonomic units. Three were host-specific and unclassified below class level, belonging to Alphaproteobacteria with affiliation to members of the Rhizobiales order (L. pertusa), Flavobacteria affiliated with members of the Elisabethkingia genus (M. oculata) and Mollicutes sequences affiliated with the Mycoplasma genus (P. arborea). In addition, gammaproteobacterial sequences within the genera Sulfitobacter and Oleispira were found across all three deep-water coral taxa. Although highly abundant in the coral microbiomes, these sequences accounted for <0.1% of the surrounding bacterioplankton, supporting specific relationships. We combined this information with previous studies, undertaking a meta-data analysis of 165 widespread samples across coral hosts and habitats. Patterns in bacterial diversity indicated enrichment of distinct uncultured species in coral microbiomes that differed among deep (>200 m), mesophotic (30–200 m) and shallow (<30 m) reefs.

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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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Connecting structure to function with the recovery of over 1000 high-quality metagenome-assembled genomes from activated sludge using long-read sequencing

Nature Communications ◽

10.1038/s41467-021-22203-2 ◽

2021 ◽

Vol 12 (1) ◽

Cited By ~ 2

Author(s):

Caitlin M. Singleton ◽

Francesca Petriglieri ◽

Jannie M. Kristensen ◽

Rasmus H. Kirkegaard ◽

Thomas Y. Michaelsen ◽

...

Keyword(s):

16S Rrna ◽

Wastewater Treatment Plants ◽

In Situ Hybridisation ◽

Amplicon Sequencing ◽

Rrna Genes ◽

Fluorescence In Situ Hybridisation ◽

Sequencing Data ◽

High Quality ◽

16S Rrna Amplicon Sequencing ◽

Long Read

AbstractMicroorganisms play crucial roles in water recycling, pollution removal and resource recovery in the wastewater industry. The structure of these microbial communities is increasingly understood based on 16S rRNA amplicon sequencing data. However, such data cannot be linked to functional potential in the absence of high-quality metagenome-assembled genomes (MAGs) for nearly all species. Here, we use long-read and short-read sequencing to recover 1083 high-quality MAGs, including 57 closed circular genomes, from 23 Danish full-scale wastewater treatment plants. The MAGs account for ~30% of the community based on relative abundance, and meet the stringent MIMAG high-quality draft requirements including full-length rRNA genes. We use the information provided by these MAGs in combination with >13 years of 16S rRNA amplicon sequencing data, as well as Raman microspectroscopy and fluorescence in situ hybridisation, to uncover abundant undescribed lineages belonging to important functional groups.

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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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Handling of spurious sequences affects the outcome of high-throughput 16S rRNA gene amplicon profiling

ISME Communications ◽

10.1038/s43705-021-00033-z ◽

2021 ◽

Vol 1 (1) ◽

Author(s):

Sandra Reitmeier ◽

Thomas C. A. Hitch ◽

Nicole Treichel ◽

Nikolaos Fikas ◽

Bela Hausmann ◽

...

Keyword(s):

16S Rrna ◽

16S Rrna Gene ◽

Amplicon Sequencing ◽

Rrna Gene ◽

Diversity Analysis ◽

Careful Attention ◽

Operational Taxonomic Units ◽

Basic Concepts ◽

Gnotobiotic Mice ◽

Mock Communities

Abstract16S rRNA gene amplicon sequencing is a popular approach for studying microbiomes. However, some basic concepts have still not been investigated comprehensively. We studied the occurrence of spurious sequences using defined microbial communities based on data either from the literature or generated in three sequencing facilities and analyzed via both operational taxonomic units (OTUs) and amplicon sequence variants (ASVs) approaches. OTU clustering and singleton removal, a commonly used approach, delivered approximately 50% (mock communities) to 80% (gnotobiotic mice) spurious taxa. The fraction of spurious taxa was generally lower based on ASV analysis, but varied depending on the gene region targeted and the barcoding system used. A relative abundance of 0.25% was found as an effective threshold below which the analysis of spurious taxa can be prevented to a large extent in both OTU- and ASV-based analysis approaches. Using this cutoff improved the reproducibility of analysis, i.e., variation in richness estimates was reduced by 38% compared with singleton filtering using six human fecal samples across seven sequencing runs. Beta-diversity analysis of human fecal communities was markedly affected by both the filtering strategy and the type of phylogenetic distances used for comparison, highlighting the importance of carefully analyzing data before drawing conclusions on microbiome changes. In summary, handling of artifact sequences during bioinformatic processing of 16S rRNA gene amplicon data requires careful attention to avoid the generation of misleading findings. We propose the concept of effective richness to facilitate the comparison of alpha-diversity across studies.

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Introducing mothur: Open-Source, Platform-Independent, Community-Supported Software for Describing and Comparing Microbial Communities

Applied and Environmental Microbiology ◽

10.1128/aem.01541-09 ◽

2009 ◽

Vol 75 (23) ◽

pp. 7537-7541 ◽

Cited By ~ 11597

Author(s):

Patrick D. Schloss ◽

Sarah L. Westcott ◽

Thomas Ryabin ◽

Justine R. Hall ◽

Martin Hartmann ◽

...

Keyword(s):

16S Rrna ◽

Software Package ◽

Sequence Data ◽

Rrna Gene ◽

Sequencing Data ◽

Laptop Computer ◽

Operational Taxonomic Units ◽

Β Diversity ◽

Single Piece

ABSTRACT mothur aims to be a comprehensive software package that allows users to use a single piece of software to analyze community sequence data. It builds upon previous tools to provide a flexible and powerful software package for analyzing sequencing data. As a case study, we used mothur to trim, screen, and align sequences; calculate distances; assign sequences to operational taxonomic units; and describe the α and β diversity of eight marine samples previously characterized by pyrosequencing of 16S rRNA gene fragments. This analysis of more than 222,000 sequences was completed in less than 2 h with a laptop computer.

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Great differences in performance and outcome of high-throughput sequencing data analysis platforms for fungal metabarcoding

MycoKeys ◽

10.3897/mycokeys.39.28109 ◽

2018 ◽

Vol 39 ◽

pp. 29-40 ◽

Cited By ~ 21

Author(s):

Sten Anslan ◽

R. Henrik Nilsson ◽

Christian Wurzbacher ◽

Petr Baldrian ◽

Leho Tedersoo ◽

...

Keyword(s):

High Throughput ◽

High Throughput Sequencing ◽

Computation Time ◽

Potential Effect ◽

Data Sets ◽

Sequencing Data ◽

Operational Taxonomic Units ◽

High Throughput Sequencing Data ◽

Recent Developments

Along with recent developments in high-throughput sequencing (HTS) technologies and thus fast accumulation of HTS data, there has been a growing need and interest for developing tools for HTS data processing and communication. In particular, a number of bioinformatics tools have been designed for analysing metabarcoding data, each with specific features, assumptions and outputs. To evaluate the potential effect of the application of different bioinformatics workflow on the results, we compared the performance of different analysis platforms on two contrasting high-throughput sequencing data sets. Our analysis revealed that the computation time, quality of error filtering and hence output of specific bioinformatics process largely depends on the platform used. Our results show that none of the bioinformatics workflows appears to perfectly filter out the accumulated errors and generate Operational Taxonomic Units, although PipeCraft, LotuS and PIPITS perform better than QIIME2 and Galaxy for the tested fungal amplicon dataset. We conclude that the output of each platform requires manual validation of the OTUs by examining the taxonomy assignment values.

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Dramatic differences in gut bacterial densities help to explain the relationship between diet and habitat in rainforest ants

10.1101/114512 ◽

2017 ◽

Cited By ~ 4

Author(s):

Jon G Sanders ◽

Piotr Lukasik ◽

Megan E Frederickson ◽

Jacob A Russell ◽

Ryuichi Koga ◽

...

Keyword(s):

16S Rrna ◽

Microbial Diversity ◽

Tropical Rainforest ◽

Amplicon Sequencing ◽

Sequencing Data ◽

Lowland Tropical Forest ◽

16S Rrna Amplicon Sequencing ◽

Microbial Symbionts ◽

Microbial Symbiosis ◽

Diversity Profiles

AbstractAbundance is a key parameter in microbial ecology, and important to estimates of potential metabolite flux, impacts of dispersal, and sensitivity of samples to technical biases such as laboratory contamination. However, modern amplicon-based sequencing techniques by themselves typically provide no information about the absolute abundance of microbes. Here, we use fluorescence microscopy and quantitative PCR as independent estimates of microbial abundance to test the hypothesis that microbial symbionts have enabled ants to dominate tropical rainforest canopies by facilitating herbivorous diets, and compare these methods to microbial diversity profiles from 16S rRNA amplicon sequencing. Through a systematic survey of ants from a lowland tropical forest, we show that the density of gut microbiota varies across several orders of magnitude among ant lineages, with median individuals from many genera only marginally above detection limits. Supporting the hypothesis that microbial symbiosis is important to dominance in the canopy, we find that the abundance of gut bacteria is positively correlated with stable isotope proxies of herbivory among canopy-dwelling ants, but not among ground-dwelling ants. Notably, these broad findings are much more evident in the quantitative data than in the 16S rRNA sequencing data. Our results help to resolve a longstanding question in tropical rainforest ecology, and have broad implications for the interpretation of sequence-based surveys of microbial diversity.

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Lactococcus lactis Diversity Revealed by Targeted Amplicon Sequencing of purR Gene, Metabolic Comparisons and Antimicrobial Properties in an Undefined Mixed Starter Culture Used for Soft-Cheese Manufacture

Foods ◽

10.3390/foods9050622 ◽

2020 ◽

Vol 9 (5) ◽

pp. 622

Author(s):

Sabrina Saltaji ◽

Olivier Rué ◽

Valérie Sopena ◽

Sophie Sablé ◽

Fatoumata Tambadou ◽

...

Keyword(s):

Microbial Diversity ◽

Starter Culture ◽

Antimicrobial Properties ◽

Amplicon Sequencing ◽

Antimicrobial Activities ◽

Operational Taxonomic Units ◽

Soft Cheese ◽

Culture Independent ◽

Identification Of Species ◽

Species Specific

The undefined mixed starter culture (UMSC) is used in the manufacture of cheeses. Deciphering UMSC microbial diversity is important to optimize industrial processes. The UMSC was studied using culture-dependent and culture-independent based methods. MALDI-TOF MS enabled identification of species primarily from the Lactococcus genus. Comparisons of carbohydrate metabolism profiles allowed to discriminate five phenotypes of Lactococcus (n = 26/1616). The 16S sequences analysis (V1–V3, V3–V4 regions) clustered the UMSC microbial diversity into two Lactococcus operational taxonomic units (OTUs). These clustering results were improved with the DADA2 algorithm on the housekeeping purR sequences. Five L. lactis variants were detected among the UMSC. The whole-genome sequencing of six isolates allowed for the identification of the lactis subspecies using Illumina® (n = 5) and Pacbio® (n = 1) technologies. Kegg analysis confirmed the L. lactis species-specific niche adaptations and highlighted a progressive gene pseudogenization. Then, agar spot tests and agar well diffusion assays were used to assess UMSC antimicrobial activities. Of note, isolate supernatants (n = 34/1616) were shown to inhibit the growth of Salmonella ser. Typhimurium CIP 104115, Lactobacillus sakei CIP 104494, Staphylococcus aureus DSMZ 13661, Enterococcus faecalis CIP103015 and Listeria innocua CIP 80.11. Collectively, these results provide insightful information about UMSC L. lactis diversity and revealed a potential application as a bio-protective starter culture.

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Natrix: a Snakemake-based workflow for processing, clustering, and taxonomically assigning amplicon sequencing reads

BMC Bioinformatics ◽

10.1186/s12859-020-03852-4 ◽

2020 ◽

Vol 21 (1) ◽

Author(s):

Marius Welzel ◽

Anja Lange ◽

Dominik Heider ◽

Michael Schwarz ◽

Bernd Freisleben ◽

...

Keyword(s):

High Throughput Sequencing ◽

Workflow Management ◽

Amplicon Sequencing ◽

Version Control ◽

Marker Genes ◽

Sequencing Data ◽

Taxonomic Assignment ◽

Ecological Processes ◽

Link Type ◽

User Friendly

Abstract Background Sequencing of marker genes amplified from environmental samples, known as amplicon sequencing, allows us to resolve some of the hidden diversity and elucidate evolutionary relationships and ecological processes among complex microbial communities. The analysis of large numbers of samples at high sequencing depths generated by high throughput sequencing technologies requires efficient, flexible, and reproducible bioinformatics pipelines. Only a few existing workflows can be run in a user-friendly, scalable, and reproducible manner on different computing devices using an efficient workflow management system. Results We present Natrix, an open-source bioinformatics workflow for preprocessing raw amplicon sequencing data. The workflow contains all analysis steps from quality assessment, read assembly, dereplication, chimera detection, split-sample merging, sequence representative assignment (OTUs or ASVs) to the taxonomic assignment of sequence representatives. The workflow is written using Snakemake, a workflow management engine for developing data analysis workflows. In addition, Conda is used for version control. Thus, Snakemake ensures reproducibility and Conda offers version control of the utilized programs. The encapsulation of rules and their dependencies support hassle-free sharing of rules between workflows and easy adaptation and extension of existing workflows. Natrix is freely available on GitHub (https://github.com/MW55/Natrix) or as a Docker container on DockerHub (https://hub.docker.com/r/mw55/natrix). Conclusion Natrix is a user-friendly and highly extensible workflow for processing Illumina amplicon data.

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