Molecular control of polyene macrolide biosynthesis: direct binding of the regulator PimM to eight promoters of pimaricin genes and identification of binding boxes.

ABSTRACT: Control of polyene macrolide production in Streptomyces natalensis is mediated by the transcriptional activator PimM. This regulator, which combines an N-terminal PAS domain with a C-terminal helix-turn-helix motif, is highly conserved among polyene biosynthetic gene clusters. PimM, truncated forms of the protein without the PAS domain (PimM(ΔPAS)), and forms containing just the DNA-binding domain (DBD) (PimM(DBD)) were overexpressed in Escherichia coli as GST-fused proteins. GST-PimM binds directly to eight promoters of the pimaricin cluster, as demonstrated by electrophoretic mobility shift assays. Assays with truncated forms of the protein revealed that the PAS domain does not mediate specificity or the distinct recognition of target genes, which rely on the DBD domain, but significantl

SUBMITTER: Santos-Aberturas J 

PROVIDER: S-EPMC3059063 | biostudies-literature | 2011 Mar

REPOSITORIES: biostudies-literature