Comparative Analyses of Cytochrome P450s and Those Associated with Secondary Metabolism in Bacillus Species.

Cytochrome P450 monooxygenases (CYPs/P450s) are among the most catalytically-diverse enzymes, capable of performing enzymatic reactions with chemo-, regio-, and stereo-selectivity. Our understanding of P450s' role in secondary metabolite biosynthesis is becoming broader. Among bacteria, Bacillus species are known to produce secondary metabolites, and recent studies have revealed the presence of secondary metabolite biosynthetic gene clusters (BGCs) in these species. However, a comprehensive comparative analysis of P450s and P450s involved in the synthesis of secondary metabolites in Bacillus species has not been reported. This study intends to address these two research gaps. In silico analysis of P450s in 128 Bacillus species revealed the presence of 507 P450s that can be grouped into 13 P450 families and 28 subfamilies. No P450 family was found to be conserved in Bacillus species. Bacillus species were found to have lower numbers of P450s, P450 families and subfamilies, and a lower P450 diversity percentage compared to mycobacterial species. This study revealed that a large number of P450s (112 P450s) are part of different secondary metabolite BGCs, and also identified an association between a specific P450 family and secondary metabolite BGCs in Bacillus species. This study opened new vistas for further characterization of secondary metabolite BGCs, especially P450s in Bacillus species.