Complete nucleotide sequence analysis and identification of 7-cyano-7-deazaguanine (PreQ₀) biosynthesis-related genes in the novel Bacillus subtilis-infecting Siphoviridae family phage BSP7

In this study, bacteriophage BSP7, a novel Bacillus subtilis-infecting member of the family Siphoviridae, was isolated from a Korean soybean-based fermented food, Deonjang, using B. subtilis ATCC 21336 as a host. The genome is 55,455 bp long with 39.92% G+C content. A total of 70 ORFs with no tRNA were detected in the genome. A distinct feature of the BSP7 genome among B. subtilis-infecting Siphoviridae family phages is the presence of putative ORFs related to biosynthesis of 7-cyano-7-deazaguanine (PreQ₀), a precursor of queuosine and archaeosine biosynthesis. Bioinformatic analysis revealed that the genome of BSP7 does not exhibit any significant similarities to other phages with sequences in the NCBI database. A comparative genomic analysis also confirmed the uniqueness of BSP7 within the family Siphoviridae.