scholarly journals Substrate-Specific Clades of Active Marine Methylotrophs Associated with a Phytoplankton Bloom in a Temperate Coastal Environment

2008 ◽  
Vol 74 (23) ◽  
pp. 7321-7328 ◽  
Author(s):  
Josh D. Neufeld ◽  
Rich Boden ◽  
Hélène Moussard ◽  
Hendrik Schäfer ◽  
J. Colin Murrell

ABSTRACT Marine microorganisms that consume one-carbon (C1) compounds are poorly described, despite their impact on global climate via an influence on aquatic and atmospheric chemistry. This study investigated marine bacterial communities involved in the metabolism of C1 compounds. These communities were of relevance to surface seawater and atmospheric chemistry in the context of a bloom that was dominated by phytoplankton known to produce dimethylsulfoniopropionate. In addition to using 16S rRNA gene fingerprinting and clone libraries to characterize samples taken from a bloom transect in July 2006, seawater samples from the phytoplankton bloom were incubated with 13C-labeled methanol, monomethylamine, dimethylamine, methyl bromide, and dimethyl sulfide to identify microbial populations involved in the turnover of C1 compounds, using DNA stable isotope probing. The [13C]DNA samples from a single time point were characterized and compared using denaturing gradient gel electrophoresis (DGGE), fingerprint cluster analysis, and 16S rRNA gene clone library analysis. Bacterial community DGGE fingerprints from 13C-labeled DNA were distinct from those obtained with the DNA of the nonlabeled community DNA and suggested some overlap in substrate utilization between active methylotroph populations growing on different C1 substrates. Active methylotrophs were affiliated with Methylophaga spp. and several clades of undescribed Gammaproteobacteria that utilized methanol, methylamines (both monomethylamine and dimethylamine), and dimethyl sulfide. rRNA gene sequences corresponding to populations assimilating 13C-labeled methyl bromide and other substrates were associated with members of the Alphaproteobacteria (e.g., the family Rhodobacteraceae), the Cytophaga-Flexibacter-Bacteroides group, and unknown taxa. This study expands the known diversity of marine methylotrophs in surface seawater and provides a comprehensive data set for focused cultivation and metagenomic analyses in the future.

2007 ◽  
Vol 73 (20) ◽  
pp. 6682-6685 ◽  
Author(s):  
Daniel P. R. Herlemann ◽  
Oliver Geissinger ◽  
Andreas Brune

ABSTRACT The bacterial candidate phylum Termite Group I (TG-1) presently consists mostly of “Endomicrobia,” which are endosymbionts of flagellate protists occurring exclusively in the hindguts of termites and wood-feeding cockroaches. Here, we show that public databases contain many, mostly undocumented 16S rRNA gene sequences from other habitats that are affiliated with the TG-1 phylum but are only distantly related to “Endomicrobia.” Phylogenetic analysis of the expanded data set revealed several diverse and deeply branching lineages comprising clones from many different habitats. In addition, we designed specific primers to explore the diversity and environmental distribution of bacteria in the TG-1 phylum.


2020 ◽  
Vol 9 (24) ◽  
Author(s):  
Sangam Kandel ◽  
Supaphen Sripiboon ◽  
Piroon Jenjaroenpun ◽  
David W. Ussery ◽  
Intawat Nookaew ◽  
...  

ABSTRACT Here, we present a 16S rRNA gene amplicon sequence data set and profiles demonstrating the bacterial diversity of baby and adult elephants from four different geographical locations in Thailand. The dominant phyla among baby and adult elephants were Bacteroidetes, Firmicutes, Proteobacteria, Kiritimatiellaeota, Euryarchaeota, and Tenericutes.


mBio ◽  
2018 ◽  
Vol 9 (2) ◽  
pp. e00319-18 ◽  
Author(s):  
Scott Sherrill-Mix ◽  
Kevin McCormick ◽  
Abigail Lauder ◽  
Aubrey Bailey ◽  
Laurie Zimmerman ◽  
...  

ABSTRACT Classical ecology provides principles for construction and function of biological communities, but to what extent these apply to the animal-associated microbiota is just beginning to be assessed. Here, we investigated the influence of several well-known ecological principles on animal-associated microbiota by characterizing gut microbial specimens from bilaterally symmetrical animals (Bilateria) ranging from flies to whales. A rigorously vetted sample set containing 265 specimens from 64 species was assembled. Bacterial lineages were characterized by 16S rRNA gene sequencing. Previously published samples were also compared, allowing analysis of over 1,098 samples in total. A restricted number of bacterial phyla was found to account for the great majority of gut colonists. Gut microbial composition was associated with host phylogeny and diet. We identified numerous gut bacterial 16S rRNA gene sequences that diverged deeply from previously studied taxa, identifying opportunities to discover new bacterial types. The number of bacterial lineages per gut sample was positively associated with animal mass, paralleling known species-area relationships from island biogeography and implicating body size as a determinant of community stability and niche complexity. Samples from larger animals harbored greater numbers of anaerobic communities, specifying a mechanism for generating more-complex microbial environments. Predictions for species/abundance relationships from models of neutral colonization did not match the data set, pointing to alternative mechanisms such as selection of specific colonists by environmental niche. Taken together, the data suggest that niche complexity increases with gut size and that niche selection forces dominate gut community construction. IMPORTANCE The intestinal microbiome of animals is essential for health, contributing to digestion of foods, proper immune development, inhibition of pathogen colonization, and catabolism of xenobiotic compounds. How these communities assemble and persist is just beginning to be investigated. Here we interrogated a set of gut samples from a wide range of animals to investigate the roles of selection and random processes in microbial community construction. We show that the numbers of bacterial species increased with the weight of host organisms, paralleling findings from studies of island biogeography. Communities in larger organisms tended to be more anaerobic, suggesting one mechanism for niche diversification. Nonselective processes enable specific predictions for community structure, but our samples did not match the predictions of the neutral model. Thus, these findings highlight the importance of niche selection in community construction and suggest mechanisms of niche diversification.


2011 ◽  
Vol 61 (4) ◽  
pp. 969-973 ◽  
Author(s):  
Liping Wang ◽  
Qiliang Lai ◽  
Yuanyuan Fu ◽  
Hua Chen ◽  
Wanpeng Wang ◽  
...  

A taxonomic study was carried out on strain 10-D-4T, which was isolated from a crude oil-degrading consortium enriched from surface seawater collected around Xiamen Island, PR China. Strain 10-D-4T grew optimally at pH 7.0–8.0 and at 25 °C. The 16S rRNA gene sequence of strain 10-D-4T showed the highest similarity to those of Idiomarina salinarum ISL-52T (94.6 %), Idiomarina tainanensis PIN1T (94.2 %) and Idiomarina seosinensis CL-SP19T (94.1 %), and showed lower similarity (92.3–94.0 %) to other members of the genus Idiomarina. The major isoprenoid quinone was ubiquinone 8 (Q-8). The major fatty acids were iso-C13 : 0 (5.2 %), iso-C15 : 0 (15.3 %), C16 : 0 (14.3 %), summed feature 3 (C16 : 1ω6c and/or C16 : 1ω7c) (6.6 %), iso-C17 : 0 (15.4 %) and C18 : 1ω7c (13.5 %). The G+C content of the chromosomal DNA was 50.4 mol%. Phylogenetic analysis based on 16S rRNA gene sequences, together with data from phenotypic and chemotaxonomic characterization, revealed that strain 10-D-4T represents a novel species of the genus Idiomarina, for which the name Idiomarina xiamenensis sp. nov. is proposed. The type strain is 10-D-4T ( = CCTCC AB 209061T  = LMG 25227T  = MCCC 1A01370T). We also propose the transfer of Pseudidiomarina aestuarii, described recently, to the genus Idiomarina as Idiomarina aestuarii comb. nov. (type strain KYW314T  = KCTC 22740T  = JCM 16344T).


2019 ◽  
Author(s):  
Pauline C. Göller ◽  
Jose M. Haro-Moreno ◽  
Francisco Rodriguez-Valera ◽  
Martin J. Loessner ◽  
Elena Gómez-Sanz

AbstractBackgroundBacteriophages are the most numerous biological entities on earth and play a crucial role in shaping microbial communities. Investigating the bacteriophage community from soil samples will shed light not only on the yet largely unknown phage diversity, but also may result in novel insights into phage biology and functioning. Unfortunately, the study of soil viromes lags far behind any other ecological model system, due to the heterogeneous soil matrix that rises major technical difficulties in the extraction process. Resolving these technical challenges and establishing a standardized extraction protocol is therefore a fundamental prerequisite for replicable results and comparative virome studies.ResultsWe here report the optimization of protocols for extraction of bacteriophage DNA from soil preceding metagenomic analysis such that the protocol can equally be harnessed for phage isolation. As an optimization strategy, soil samples were spiked with a viral community consisting of phages from different families (106 PFU/g soil): Listeria phage ΦA511 (Myovirus), Staphylococcus phage Φ2638AΔLCR (Siphovirus), and Escherichia phage ΦT7 (Podovirus). The efficacy of bacteriophage (i) elution, (ii) filtration, (iii) concentration, and (iv) DNA extraction methods was tested. Successful extraction routes were selected based on spiked phage recovery and low bacterial 16S rRNA gene contaminants. Natural agricultural soil viromes were then extracted with the optimized methods and shotgun sequenced. Our approach yielded sufficient amounts of inhibitor-free viral DNA for non-amplification dependent sequencing and low 16S rRNA gene contamination levels (≤ 0.2 ‰). Compared to previously published protocols, the number of bacterial read contamination was decreased by 65 %. In addition, 468 novel circularized soil phage genomes in size up to 235 kb were obtained from over 29,000 manually identified viral contigs, promising the discovery of a large, previously inaccessible viral diversity.ConclusionWe have shown a dramatically enhanced extraction of the soil phage community by protocol optimization that has proven robustness in both a culture-depended as well as through metaviromic analysis. Our huge data set of manually curated soil viral contigs roughly doubles the amount of currently available soil virome data, and provide insights into the yet largely undescribed soil viral sequence space.


mBio ◽  
2018 ◽  
Vol 9 (3) ◽  
Author(s):  
Marc A. Sze ◽  
Patrick D. Schloss

ABSTRACTAn increasing body of literature suggests that both individual and collections of bacteria are associated with the progression of colorectal cancer. As the number of studies investigating these associations increases and the number of subjects in each study increases, a meta-analysis to identify the associations that are the most predictive of disease progression is warranted. We analyzed previously published 16S rRNA gene sequencing data collected from feces and colon tissue. We quantified the odds ratios (ORs) for individual bacterial taxa that were associated with an individual having tumors relative to a normal colon. Among the fecal samples, there were no taxa that had significant ORs associated with adenoma and there were 8 taxa with significant ORs associated with carcinoma. Similarly, among the tissue samples, there were no taxa that had a significant OR associated with adenoma and there were 3 taxa with significant ORs associated with carcinoma. Among the significant ORs, the association between individual taxa and tumor diagnosis was equal to or below 7.11. Because individual taxa had limited association with tumor diagnosis, we trained Random Forest classification models using only the taxa that had significant ORs, using the entire collection of taxa found in each study, and using operational taxonomic units defined based on a 97% similarity threshold. All training approaches yielded similar classification success as measured using the area under the curve. The ability to correctly classify individuals with adenomas was poor, and the ability to classify individuals with carcinomas was considerably better using sequences from feces or tissue.IMPORTANCEColorectal cancer is a significant and growing health problem in which animal models and epidemiological data suggest that the colonic microbiota have a role in tumorigenesis. These observations indicate that the colonic microbiota is a reservoir of biomarkers that may improve our ability to detect colonic tumors using noninvasive approaches. This meta-analysis identifies and validates a set of 8 bacterial taxa that can be used within a Random Forest modeling framework to differentiate individuals as having normal colons or carcinomas. When models trained using one data set were tested on other data sets, the models performed well. These results lend support to the use of fecal biomarkers for the detection of tumors. Furthermore, these biomarkers are plausible candidates for further mechanistic studies into the role of the gut microbiota in tumorigenesis.


2015 ◽  
Vol 65 (Pt_4) ◽  
pp. 1127-1132 ◽  
Author(s):  
Jing Liang ◽  
Ji Liu ◽  
Xiao-Hua Zhang

A Gram-stain-negative, strictly aerobic and rod-shaped motile bacterium with peritrichous flagella, designated strain LZB041T, was isolated from offshore surface seawater of the East China Sea. Phylogenetic analysis based on 16S rRNA gene sequences indicated that strain LZB041T formed a lineage within the family ‘ Aurantimonadaceae ’ that was distinct from the most closely related genera Aurantimonas (96.0–96.4 % 16S rRNA gene sequence similarity) and Aureimonas (94.5–96.0 %). Optimal growth occurred in the presence of 1–7 % (w/v) NaCl, at pH 7.0–8.0 and at 28–37 °C. Ubiquinone-10 was the predominant respiratory quinone. The major fatty acids (>10 % of total fatty acids) were C18 : 1ω7c and/or C18 : 1ω6c (summed feature 8) and cyclo-C19 : 0ω8c. The major polar lipids were phosphatidylglycerol, diphosphatidylglycerol, phosphatidylcholine, phosphatidylethanolamine, phosphatidylmonomethylethanolamine, one unknown aminolipid, one unknown phospholipid and one unknown polar lipid. The DNA G+C content of strain LZB041T was 71.3 mol%. On the basis of polyphasic analysis, strain LZB041T is considered to represent a novel species of a new genus in the class Alphaproteobacteria , for which the name Jiella aquimaris gen. nov., sp. nov. is proposed. The type strain of the type species is LZB041T ( = JCM 30119T = MCCC 1K00255T).


mSphere ◽  
2018 ◽  
Vol 3 (5) ◽  
Author(s):  
Robin R. Rohwer ◽  
Joshua J. Hamilton ◽  
Ryan J. Newton ◽  
Katherine D. McMahon

ABSTRACT Taxonomy assignment of freshwater microbial communities is limited by the minimally curated phylogenies used for large taxonomy databases. Here we introduce TaxAss, a taxonomy assignment workflow that classifies 16S rRNA gene amplicon data using two taxonomy reference databases: a large comprehensive database and a small ecosystem-specific database rigorously curated by scientists within a field. We applied TaxAss to five different freshwater data sets using the comprehensive SILVA database and the freshwater-specific FreshTrain database. TaxAss increased the percentage of the data set classified compared to using only SILVA, especially at fine-resolution family to species taxon levels, while across the freshwater test data sets classifications increased by as much as 11 to 40% of total reads. A similar increase in classifications was not observed in a control mouse gut data set, which was not expected to contain freshwater bacteria. TaxAss also maintained taxonomic richness compared to using only the FreshTrain across all taxon levels from phylum to species. Without TaxAss, most organisms not represented in the FreshTrain were unclassified, but at fine taxon levels, incorrect classifications became significant. We validated TaxAss using simulated amplicon data derived from full-length clone libraries and found that 96 to 99% of test sequences were correctly classified at fine resolution. TaxAss splits a data set’s sequences into two groups based on their percent identity to reference sequences in the ecosystem-specific database. Sequences with high similarity to sequences in the ecosystem-specific database are classified using that database, and the others are classified using the comprehensive database. TaxAss is free and open source and is available at https://www.github.com/McMahonLab/TaxAss. IMPORTANCE Microbial communities drive ecosystem processes, but microbial community composition analyses using 16S rRNA gene amplicon data sets are limited by the lack of fine-resolution taxonomy classifications. Coarse taxonomic groupings at the phylum, class, and order levels lump ecologically distinct organisms together. To avoid this, many researchers define operational taxonomic units (OTUs) based on clustered sequences, sequence variants, or unique sequences. These fine-resolution groupings are more ecologically relevant, but OTU definitions are data set dependent and cannot be compared between data sets. Microbial ecologists studying freshwater have curated a small, ecosystem-specific taxonomy database to provide consistent and up-to-date terminology. We created TaxAss, a workflow that leverages this database to assign taxonomy. We found that TaxAss improves fine-resolution taxonomic classifications (family, genus, and species). Fine taxonomic groupings are more ecologically relevant, so they provide an alternative to OTU-based analyses that is consistent and comparable between data sets.


PLoS ONE ◽  
2017 ◽  
Vol 12 (3) ◽  
pp. e0173408 ◽  
Author(s):  
Niranjan Nitin Parulekar ◽  
Pandurang Kolekar ◽  
Andrew Jenkins ◽  
Synne Kleiven ◽  
Hans Utkilen ◽  
...  

mSystems ◽  
2018 ◽  
Vol 3 (3) ◽  
Author(s):  
Clifford J. Beall ◽  
Alisha G. Campbell ◽  
Ann L. Griffen ◽  
Mircea Podar ◽  
Eugene J. Leys

ABSTRACTDespite decades of research into the human oral microbiome, many species remain uncultivated. The technique of single-cell whole-genome amplification and sequencing provides a means of deriving genome sequences for species that can be informative on biological function and suggest pathways to cultivation.Tannerella forsythiahas long been known to be highly associated with chronic periodontitis and to cause periodontitis-like symptoms in experimental animals, andTannerellasp. BU045 (human oral taxon 808) is an uncultivated relative of this organism. In this work, we extend our previous sequencing of theTannerellasp. BU063 (human oral taxon 286) genome by sequencing amplified genomes from 11 cells ofTannerellasp. BU045, including 3 genomes that are at least 90% complete.Tannerellasp. BU045 is more closely related toTannerellasp. BU063 than toT. forsythiaby gene content and average nucleotide identity. However, two independent data sets of association with periodontitis, one based on 16S rRNA gene abundance and the other based on gene expression in a metatranscriptomic data set, show thatTannerellasp. BU045 is more highly associated with disease thanTannerellasp. BU063. Comparative genomics shows genes and functions that are shared or unique to the different species, which may direct further research of the pathogenesis of chronic periodontitis.IMPORTANCEPeriodontitis (gum disease) affects 47% of adults over 30 in the United States (P. I. Eke, B. A. Dye, L. Wei, G. O. Thornton-Evans, R. J. Genco, et al., J Dent Res 91:914–920, 2012), and it cost between $39 and $396 billion worldwide in 2015 (A. J. Righolt, M. Jevdjevic, W. Marcenes, and S. Listl, J Dent Res, 17 January 2018, https://doi.org/10.1177/0022034517750572). Many bacteria associated with the disease are known only by the DNA sequence of their 16S rRNA gene. In this publication, amplification and sequencing of DNA from single bacterial cells are used to obtain nearly complete genomes ofTannerellasp. BU045, a species of bacteria that is more prevalent in patients with periodontitis than in healthy patients. Comparing the complete genome of this bacterium to genomes of related bacterial species will help to better understand periodontitis and may help to grow this organism in pure culture, which would allow a better understanding of its role in the mouth.


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