Identification of a protein-binding sequence involved in expression of an esterase gene from Streptomyces scabies

Expression of an esterase gene from Streptomyces scabies is regulated by zinc in both Streptomyces scabies and Streptomyces lividans. A specific protein-binding site was identified on an esterase promoter fragment by using an S-30 extract from S. scabies. The location of the protein-binding site was determined by gel shift assays of promoter deletion fragments and by DNase I footprinting analysis. The protein-binding site maps from nucleotides -59 to -81 relative to the start of transcription. An esterase gene construct cloned and expressed in S. lividans was used to assess the importance of the protein-binding site. Deletion of the 23-bp protein-binding site resulted in a 10-fold decrease in esterase production when cells were grown in zinc- inducing conditions. The protein-binding site may represent a region involved in positive regulation of the S. scabies esterase gene.