Bacillus clarus sp. nov. is a new Bacillus cereus group species isolated from soil

Bacillus cereus group or B. cereus sensu lato (s.l.), is comprised of Gram-positive spore-forming, rod-like bacteria that are widespread in natural environments. Although the species in this group are known to be highly related in terms of phenotypic characteristics, they display different levels of pathogenicity. Biochemical assays are therefore considered to be insufficient for accurate taxonomic classification of B. cereus group species. To facilitate accurate taxonomic classification and associated prediction of pathogenic potential, we have conducted comparative genomic analyses of publicly available genome assemblies of B. cereus group isolates. Through that, we found that an isolate previously known as B. mycoides ATCC 21929 was sufficiently distant from valid and effective type strains to be considered a putative new species. We have conducted biochemical and bioinformatic characterization of strain ATCC 21929 that had been isolated from soil in Papua New Guinea. Strain ATCC 21929 most closely resembles B. paramycoides NH24A2T, producing ANIb and DDH values of 86.70% and 34.1%, respectively. Phenotypically, isolate ATCC 21929 does not possess cytochrome c oxidase activity, and is able to grow at a range of temperatures 15{degrees}C - 43{degrees}C and at a range of pH 6 - 9. With regards to fatty acid composition, this isolate has iso-C17:0 in highest abundance. We propose the strain ATCC 21929T (=PS00077AT = PS00077BT = PSU-0922T = BHPT) as a new species named Bacillus clarus sp. nov. to facilitate accurate taxonomic classification of B. cereus group isolates.