Phosphorylation of a bacterial activator protein, OmpR, by a protein kinase, EnvZ, stimulates the transcription of the ompF and ompC genes in Escherichia coli.

The OmpR of Escherichia coli is a positive regulator specific for the ompF and ompC genes, which encode outer membrane proteins OmpF and OmpC, respectively. The EnvZ protein is a protein kinase which specifically phosphorylates the OmpR protein. In this study, the results of in vitro transcription experiments revealed that the phosphorylation of the OmpR protein by the EnvZ protein stimulates the transcription of both the ompF and ompC genes.