Abstract
The Escher ichia coli DNA-binding protein OmpR is the best characterized of those regulator proteins making up “two-component system, ” the simplest known form of bacterial signal transduction systems. Previous inspections of the E. coil genome DNA sequences have revealed that there are 15 proteins whose amino acid sequences show extensive similarities to that of OmpR (the OmpR-family of proteins). The three-dimensional structures of several OmpR-family proteins have been determined. In this review, we investigated the structures and amino acid sequences of this family of proteins. The results reveal several notable conservative varieties in their tertiary structures and functions.