Genomic Insights into Antimicrobial Biosynthetic Potential of Bacillus velezensis Isolated from Traditional Peruvian Tocosh

Tocosh, a traditional Peruvian fermented potato product, is known for its health-promoting properties, including its antioxidant, anti-inflammatory, probiotic, and antibiotic effects, which have popularized its consumption, particularly in rural areas. To gain a better understanding of its antimicrobial properties, this study aimed to perform a comprehensive whole-genome analysis and functional assessment of the <i>Bacillus velezensis</i> TCSH0001 strain isolated from tocosh. The isolate was identified through whole-genome sequencing using the MinION nanopore platform. AntiSMASH analysis revealed nine biosynthetic gene clusters (BGCs) potentially responsible for producing secondary metabolites with antibiotic potential. Notably, seven BGCs showed a 100% similarity to known clusters involved in the biosynthesis of polyketide synthases (PKSs) and non-ribosomal peptides (NRPSs), including difficidin, bacillibactin, bacilysin, macrolactin H, bacillaene, fengycin, and bacillomycin D. <i>In vitro</i> analysis revealed antimicrobial activity against <i>S. aureus</i> strains. In addition, RT-qPCR indicated that the expression of the <i>baeJ</i> (bacillaene), <i>bmyA</i> (bacillomycin D), and <i>pks2A</i> (macrolactin H) occurs predominantly during the exponential growth phase. Our results suggest that this <i>B. velezensis</i> strain has the capacity to produce a diverse array of bioactive compounds, supporting the traditional use of tocosh as a natural antimicrobial agent, and revealing the potential of the strain as a high NRPS producer.