화학공학소재연구정보센터
Applied Microbiology and Biotechnology, Vol.104, No.23, 10191-10202, 2020
Identification of a gene fromStreptomyces rimosusM527 negatively affecting rimocidin biosynthesis and morphological differentiation
The polyene macrolide rimocidin, produced byStreptomyces rimosusM527, was found to be highly effective against a broad range of fungal plant pathogens. Current understanding of the regulatory mechanism of rimocidin biosynthesis and morphological differentiation inS. rimosusM527 is limited. NsdA is considered a negative regulator involved in morphological differentiation and biosynthesis of secondary metabolites in someStreptomycesspecies. In this study,nsdA(sr)was cloned fromS. rimosusM527. The role ofnsdA(sr)in rimocidin biosynthesis and morphological differentiation was investigated by gene deletion, complementation, and over-expression. A Delta nsdA(sr)mutant was obtained using CRISPR/Cas9. The mutant produced more rimocidin (46%) and accelerated morphological differentiation than the wild-type strain. Over-expression ofnsdA(sr)led to a decrease in rimocidin production and impairment of morphological differentiation. Quantitative RT-PCR analysis revealed that transcription ofrimgenes responsible for rimocidin biosynthesis was upregulated in the Delta nsdA(sr)mutant but downregulated in thensdA(sr)over-expression strain. Similar effects have been described forStreptomyces coelicolorM145 and the industrial toyocamycin-producing strainStreptomyces diastatochromogenes1628.