Multiple regulation of the galactose operon-genetic evidence for a distinct site in the galactose operon that responds to capR gene regulation in Escherichia coli K-12.

ABSTRACT: Previous results demonstrated that the capR (lon) locus, which is not linked to the gal operon, independently controls the synthesis of the gal operon enzymes and gal mRNA, i.e., galO(+)capR9 strains are derepressed 4- to 6-fold as compared to galO(+)capR(+) strains. A mutation has been isolated and localized in the galactose operator region that defines a new and distinct site of control. Mutation in this site, designated galO(capR+), causes a 4-fold increase in the galactose enzymes, galactokinase (EC 2.7.1.6) and UDP-galactose-4-epimerase (EC 5.1.3.2), in a capR(+) background. These mutants exhibit a reduced response to regulation by the unlinked regulator gene capR (lon). However, the galO(capR+) mutants are still subject to control by the galR repressor, since they can be further dere

SUBMITTER: Hua SS 

PROVIDER: S-EPMC388036 | biostudies-literature | 1974 Feb

REPOSITORIES: biostudies-literature