Draft genome sequence and potential identification of a biosurfactant from Brevibacterium casei strain LS14 an isolate from fresh water Loktak Lake

This study reports the whole-genome sequencing and sequence analysis of a bacterial isolate Brevibacterium casei strain LS14, isolated from Loktak Lake, Imphal, India. The de novo assembled genome reported in this paper featured a size of 3,809,532 bp, has GC content of 68% and contains 3602 genomic features, including 3551 protein-coding genes, 46 tRNA and 5rRNA. A biosurfactant biosynthesis gene cluster in the genome of the isolated strain was identified using AntiSMASH online tool V3.0.5 and KAAS (KEGG Automatic Annotation Server). The presence of biosurfactant was demonstrated by drop collapse, oil displacement and emulsification index. Subsequent chemical characterization using FTIR and LC–MS analyses revealed surfactin and terpene containing biosurfactant moieties. Also, the presence of genes involved in terpenoid synthesis pathway in the genome sequence may account for biosurfactant terpenoid backbone, but genes for later-stage conversion of terpenoid to biosurfactant were not ascertained.