Draft Genome Sequence of Bacillus velezensis OSY-S3, a Producer of Potent Antimicrobial Agents Active against Bacteria and Fungi.

Bacillus velezensis OSY-S3 produces anti-Listeria, anti-Escherichia coli, and antifungal compounds. Additionally, fermentate of B. velezensis OSY-S3 culture removes Staphylococcus aureus biofilms effectively. The draft genome sequence of B. velezensis OSY-S3 reported here had a genome size of ~3.90 Mb and a G+C content of 46.5%.

GENOME ANNOUNCEMENT

Bacillus spp. are known to produce a multiplicity of functional metabolites, including antimicrobial compounds (1). B. velezensis OSY-S3, a strain isolated recently from silage, produced multifunctional antimicrobial agents. Fermentate of B. velezensis OSY-S3 culture inhibited Listeria innocua on agar plate and removed Staphylococcus aureus biofilms in 96-well plates (M. M. Gerst, unpublished data). Crude cell extract from B. velezensis OSY-S3 inhibited L. innocua, Escherichia coli, Penicillium sp., Cladosporium sp., and S. aureus (M. M. Gerst, unpublished data).

The whole genome of B. velezensis OSY-S3 was sequenced at The Ohio State University Nucleic Acid Shared Resource Facility (Columbus, OH, USA) using Ion Torrent next-generation sequencing technology. Raw data, in the form of 1,170,526 reads, were de novo assembled into 104 contigs using the SPAdes version 3.10.1 genome assembler (2). The contigs were ordered against B. subtilis 916 (reference genome) using progressiveMAUVE multiple genome alignment software (3), with one N representing each gap. The maximum contig size was 192,427 bp, and the minimum size was 206 bp. The NCBI Prokaryotic Genome Annotation Pipeline was used to annotate the B. velezensis OSY-S3 draft genome. The genome mining programs BAGEL3 and antiSMASH version 4.0.3 were used to identify secondary metabolite gene clusters (4, 5).

A total of 12 secondary metabolite gene clusters were identified using antiSMASH. Among these metabolites, antimicrobial agents with similarity to surfactin (91%), macrolactin (100%), bacillaene (100%), fengycin (100%), difficidin (100%), bacillibactin (100%), and bacilysin (100%) were recognized. Two additional antimicrobial peptides, plantazolicin and LCI, were identified using BAGEL3. Genes for many of these antimicrobial agents can also be found in in the genome of B. velezensis FZB42 (previously B. amyloliquefaciens subsp. plantarum FZB42) (6). Macrolactin, bacillaene, difficidin, bacilysin, and plantazolicin are known for activity against Gram-positive bacteria (7–11). Bacillaene, difficidin, and bacilysin are active against Gram-negative bacteria (7–9). Fengycin has antifungal activity (12). Sequencing the whole genome of B. velezensis OSY-S3 provided insight into the sources of the broad antimicrobial activity exhibited by this bacterium. The capability to produce several potent antimicrobial compounds makes B. velezensis OSY-S3 a candidate strain for combating pathogenic microorganisms in food, agriculture, and medicine.

Accession number(s).

The B. velezensis OSY-S3 whole-genome sequence has been deposited in NCBI/GenBank under the accession no. CP024706. The version described in this paper is the final version.