PUB - Publikationen an der Universität Bielefeld

The search for producers of biologically active metabolites is shifting towards the study of strains from exotic biotopes. Aerobic spore-forming bacteria from the Black Sea bottom sediments are a good example of such microorganisms due to the simplicity of selective isolation, culture maintenance, and high biosynthetic activity.
**Aim**. To analyze the genome structure of Bacillus sp. ONU 553 bacterial strain, isolated from bottom sediments of the Black Sea, for its reidentification and to find genes responsible for the synthesis of biologically active compounds.
**Methods**. The obtained genomic DNA was sequenced using НiSeq 1500 equipment (Illumina). Genome assembly was performed with a Newbler 2.8 assembler, species identification with a TYGS server, for ANI calculation Ezbiocloud was used. Genome annotation was done using a PATRIC and NCBI PGAP servers, search for biosynthetic gene clusters of antibiotics and bacteriocins using antiSMASH and Bagel4 respectively. Search for pathogenicity determinant was conducted using IslandViewer, for antibiotic resistance ResFinder-3.2, prophage elements search with PHASTER.
**Results**. Established that the size of the studied genome of Bacillus sp. ONU 553 is 3 934 563 bp, the mean GC content is 46.69%. 3 953 open reading frames were revealed, 3 252 of them, i.e. 82% are identified. Determinants of six antibiotics and two bacteriocins and also four prophage-like elements were found.
**Conclusions**. The conducted studies and comparative analysis of Bacillus sp. ONU 553 strain genome, which was isolated from the Black Sea bottom sediments gives us reasons to reidentify it as Bacillus velezensis and make perspective it’s further study as potential probiotic and source of new biologically active compounds.