Complete genome of Bacillus velezensis CMT-6 and comparative genome analysis reveals lipopeptide diversity

Abstract

The complete genome sequence of Bacillus velezensis type strain CMT-6 is presented for the first time. A comparative analysis between the genome sequences of CMT-6 with the genome of Bacillus amyloliquefaciens DSM7ᵀ, B. velezensis FZB42, and Bacillus subtilis 168 revealed major differences in the lipopeptide synthesis genes. Of the above, only the CMT-6 strain possessed an integrated synthetase gene for synthesizing surfactin, iturin, and fengycin. However, CMT-6 shared 14, 12, and 10 other lipopeptide-producing genes with FZB42, DSM7ᵀ, and 168 respectively. The largest numbers of non-synonymous mutations were detected in 205 gene sequences that produced these three lipopeptides in CMT-6 and 168. Comparing CMT-6 with DSM7ᵀ, 58 non-synonymous mutations were detected in gene sequences that contributed to produce lipopeptides. In addition, InDels were identified in yczE and glnR genes. CMT-6 and FZB42 had the lowest number of non-synonymous mutations with 8 lipopeptide-related gene sequences. And InDels were identified in only yczE. The numbers of core genes, InDels, and non-synonymous mutations in genes were the main reasons for the differences in yield and variety of lipopeptides. These results will enrich the genomic resources available for B. velezensis and provide fundamental information to construct strains that can produce specific lipopeptides.