Identification and mapping of the sulphate permease promoter region in Escherichia coli.

The cys329::lac fusion linking the lacZ gene to the regulatory region of cys locus involved in sulphate transport in E. coli, was cloned and localized within the restriction map of cysA region. The region containing the cysB-dependent promoter governing the expression of sulphate transport system was identified and the direction of transcription from this promoter has been established. Two complementation groups specified by different mutations in cysA region of E. coli were found.