Phosphorylation of HPr by the bifunctional HPr kinase/P-Ser-HPr phosphatase from Lactobacillus casei controls catabolite repression and inducer exclusion but not inducer expulsion

Results reveal that HPr kinase/P-Ser-HPr phosphatase of gram-positive bacteria is a regulator protein and controls catabolic expression. Data also point out that the bifunctional enzyme may not be involved in the inducer expulsion regulatory process.