Bioinformatics Analysis of Spore Pigment Biosynthetic Gene Cluster in Streptomyces species

Abstract

Streptomyces species produces multiple secondary metabolites that account for approximately two-thirds of natural antibiotics that exhibit remarkable therapeutic attributes. Notably, the diversity of these compounds stem from the variation in gene clusters that encode their proteins. An example of a gene cluster that expresses the spore colour of Streptomyces species is whiE. Primarily, it codes for the gray spore pigment in Streptomyces coelicolor, and the locus is present in numerous Streptomyces species. Moreover, Streptomyces spp exhibits different spore colours, and the molecular basis for the variation remains unclear. This study elucidated the relationship between whiE cluster and spore colours. Firstly, 31 Streptomyces species were selected, and their genomes were retrieved from the NCBI website. Subsequently, analysis was performed for all 31 species using their RpoB proteins and the ones that had SCO5316, SCO5317, and SCO5318 WhiE proteins were identified. The findings indicated that the presence of WhiE proteins was closely related with gray, blue and green spore colours, whereas the absence was mostly associated with red and yellow spore colours, implying possible evolution of RpoB by deletion. Furthermore, the relationship pattern of spore colours was consistent in SCO5316, SCO5317, and SCO5318 RpoB trees. The yellow spore colours had a closer relationship with the red ones. Similarly, the blue spores were closely related to green ones, whereas the gray spores exhibited close relationship with all spore colours, indicating a relationship between whiE cluster and the different pigments. The findings may provide insights for designing or evolution of other PKS antibiotics.