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bioRxiv · 10.1101/2019.12.21.885665

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

Rasmussen, T. S.·Streidl, T.·Hitch, T. C. A.·Wortmann, E.·Deptula, P.·Hansen, M.·Nielsen, D. S.·Clavel, T.·Vogensen, F. K.
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Abstract

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.

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Rasmussen, T. S., Streidl, T., Hitch, T. C. A., Wortmann, E., Deptula, P., Hansen, M., Nielsen, D. S., Clavel, T., Vogensen, F. K.. 2019-12-27. Sporaefaciens musculi gen. nov., sp. nov., a novel bacterium isolated from the caecum of an obese mouse. https://doi.org/10.1101/2019.12.21.885665

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