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Thermus species are thermophilic heterotrophs, with most capable of using a variety of organic and inorganic electron donors for respiration. Here, a combined cultivation-independent and -dependent approach was used to explore the diversity of Thermus in Great Boiling Spring (GBS) and Little Hot Creek (LHC) in the US Great Basin. A cultivation-independent 16S rRNA gene survey of ten LHC sites showed that Thermus made up 0–3.5% of sequences and were predominately Thermus thermophilus. 189 Thermus isolates from GBS and LHC were affiliated with T. aquaticus (73.0%), T. oshimai (25.4%), T. sediminis (1.1%), and T. thermophilus (0.5%), with T. aquaticus and T. oshimai forming biogeographic clusters. 22 strains were selected for characterization, including chemolithotrophic oxidation of thiosulfate and arsenite, and reduction of ferric iron, polysulfide, and nitrate, revealing phenotypic diversity and broad respiratory capability within each species. PCR demonstrated the wide distribution of aerobic arsenite oxidase genes. A GBS sediment metaproteome contained sulfite oxidase and Fe3+ ABC transporter permease peptides, suggesting sulfur and iron transformations in situ. This study expands our knowledge of the physiological diversity of Thermus, suggesting widespread chemolithotrophic and anaerobic respiration phenotypes, and providing a foundation for better understanding the ecology of this genus in thermal ecosystems. [ABSTRACT FROM AUTHOR]

To understand bacterial community dynamics during the vermicomposting of lignin-rich coconut leaves using an indigenous isolate of an epigeic earthworm, Eudrilus sp., we employed amplicon-based pyrosequencing of the V1 to V3 region of the 16S rRNA genes. Total community DNA was isolated from two separate vermicomposting tanks in triplicate at four different stages of the process: pre-decomposition (15th day), initial vermicomposting (45th day), 50-70% vermicomposting (75th day) and mature vermicompost (105th day). Alpha diversity measurements revealed an increase in bacterial diversity till the 75th day, which then declined in the mature vermicompost. Beta diversity comparisons showed formation of distinct, stage-specific communities. In terms of relative abundance, the Acidobacteria, Actinobacteria, Chloroflexi, Gemmatimonadetes, Nitrospirae, Planctomycetes, TM7 and WS3 groups increased until the 50-70% vermicomposting stage (p = 0.05). During the same time, the abundance of Bacteroidetes and Proteobacteria decreased. In contrast, the levels of Firmicutes increased throughout the 105-day vermicomposting process. The distribution of the most abundant OTUs revealed that each stage of the vermicomposting process possessed its own unique microbiome. Predictions based on the OTUs present by PICRUSt suggested a functional shift in the microbiome during vermicomposting. Enzymes and pathways of lipid and lignin metabolism were predicted to be initially abundant, but by the end of the process, biosynthesis of secondary metabolites and plant beneficial properties were enriched. The study revealed that bacterial communities undergo a continuous change throughout the vermicomposting process and that certain OTUs associated with specific stages could be targets for further improvements in the process. [ABSTRACT FROM AUTHOR]

A correction to this article has been published and is linked from the HTML and PDF versions of this paper. The error has not been fixed in the paper. [ABSTRACT FROM AUTHOR]

Bats are crucial for proper functioning of an ecosystem. They provide various important services to ecosystem and environment. While, bats are well-known carrier of pathogenic viruses, their possible role as a potential carrier of pathogenic bacteria is under-explored. Here, using culture-based approach, employing multiple bacteriological media, over thousand bacteria were cultivated and identified from Rousettus leschenaultii (a frugivorous bat species), the majority of which were from the family Enterobacteriaceae and putative pathogens. Next, pathogenic potential of most frequently cultivated component of microbiome i.e. Escherichia coli was assessed to identify its known pathotypes which revealed the presence of virulent factors in many cultivated E. coli isolates. Applying in-depth bacterial community analysis using high-throughput 16 S rRNA gene sequencing, a high inter-individual variation was observed among the studied guano samples. Interestingly, a higher diversity of bacterial communities was observed in decaying guano representative. The search against human pathogenic bacteria database at 97% identity, a small proportion of sequences were found associated to well-known human pathogens. The present study thus indicates that this bat species may carry potential bacterial pathogens and advice to study the effect of these pathogens on bats itself and the probable mode of transmission to humans and other animals. [ABSTRACT FROM AUTHOR]