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Clavel, T.

Publications and source records attributed to Clavel, T..

3 recordsLinked to original sources

Arrhythmic gut microbiome signatures for risk profiling of Type-2 Diabetes

To combat the epidemic increase in Type-2-Diabetes (T2D), risk factors need to be identified. Diet, lifestyle and the gut microbiome are among the most important factors affecting metabolic health. We demonstrate in 1,976 subjects of a prospective population cohort that specific gut microbiota members show diurnal oscillations in their relative abundance and we identified 13 taxa with disrupted rhythmicity in T2D. Prediction models based on this signature classified T2D with an area under the curve of 73%. BMI as microbiota-independent risk marker further improved diagnostic classification of T2D. The validity of this arrhythmic risk signature to predict T2D was confirmed in 699 KORA subjects five years after initial sampling. Shotgun metagenomic analysis linked 26 pathways associated with xenobiotic, amino acid, fatty acid, and taurine metabolism to the diurnal oscillation of gut bacteria. In summary, we determined a cohort-specific risk pattern of arrhythmic taxa which significantly contributes to the classification and prediction of T2D, highlighting the importance of circadian rhythmicity of the microbiome in targeting metabolic human diseases.

microbiology

Sporaefaciens musculi gen. nov., sp. nov., a novel bacterium isolated from the caecum of an obese mouse

A bacterial strain, designated WCA-9-b2, was isolated from the caecal content of an 18-week-old obese C57BL/6NTac male mouse. According to phenotypic analyses, the isolate is rod-shaped, Gram-positive, strictly anaerobic, spore-forming and non-motile under the conditions tested. Bacterial colonies were irregular and non-pigmented. Analysis of the 16S rRNA gene indicated that the isolate belonged to the family Lachnospiraceae with Clostridium scindens ATTC 35704 (94.9% sequence identity) and Dorea formicigenerans ATCC 27755 (94.8%) being the closest relatives. Whole genome sequencing showed average nucleotide identity (ANI) ranging from 69.80-74.23% and percentage of conserved proteins (POCP) values < 50% against the nine closest relatives. The genome-based G+C content of genomic DNA was 44.4%. The predominant metabolic end products of glucose fermentation were acetate and succinate. Based on these data, we propose that strain WCA-9-b2 represents a novel species within a novel genus, for which the name Sporaefaciens musculi gen. nov., sp. nov. is proposed. The type strain is WCA-9-b2T (=DSM 106039T = CCUG pending IDT). RepositoriesThe GenBank accession number for the 16S rRNA gene sequence of strain WCA-9-b2T is MN756014, and the accession number for the genome assembly is PRJNA592877. Raw sequencing Illumina NextSeq (PRJEB35655) and ONT MinION (PRJEB35656) data can be accessed at EMBL-EBI.

microbiology

An integrated metagenome catalog reveals novel insights into the murine gut microbiome

The vast complexity of host-associated microbial ecosystems requires generation of host-specific gene catalogs to survey the functions and diversity of these communities. We generated a comprehensive resource, the integrated mouse gut metagenome catalog (iMGMC), comprising 4.6 million unique genes and 660 high-quality metagenome-assembled genomes (MAGs) linked to reconstructed full-length 16S rRNA gene sequences. iMGMC enables unprecedented coverage and taxonomic resolution, i.e. more than 89% of the identified taxa are not represented in any other databases. The tool (github.com/tillrobin/iMGMC) allowed characterizing the diversity and functions of prevalent and previously unknown microbial community members along the gastrointestinal tract. Moreover, we show that integration of MAGs and 16S rRNA gene data allows a more accurate prediction of functional profiles of communities than based on 16S rRNA amplicons alone. Integrated gene catalogs such as iMGMC are needed to enhance the resolution of numerous existing and future sequencing-based studies.

microbiology