Mutations That Affect Separate Functions of OmpR the Phosphorylated Regulator of Porin Transcription in Escherichia Coli

J Mol Biol. 1993 May 20;231(2):261-73. doi: 10.1006/jmbi.1993.1281.


OmpR is a member of a family of bacterial transcriptional regulators whose activity is controlled by phosphorylation. It regulates the transcription of two genes, serving as an activator of ompC, and as both an activator and a repressor of ompF. A previously isolated collection of ompR mutations was analyzed for the effect of each on the expression of both genes simultaneously. The results of this analysis indicate that the activation, repression, and DNA binding functions of OmpR can be disrupted independently, and that mutations interfering with each of these functions cluster within the sequence of the OmpR protein. The nature of these mutations is discussed in terms of the mechanisms by which OmpR regulates transcription, and potentially similar mechanisms operating within closely related response regulators.

Publication types

  • Comparative Study
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Amino Acid Sequence
  • Bacterial Outer Membrane Proteins / biosynthesis*
  • Bacterial Outer Membrane Proteins / genetics*
  • Base Sequence
  • DNA Mutational Analysis
  • DNA-Binding Proteins / genetics
  • DNA-Binding Proteins / metabolism
  • Diploidy
  • Escherichia coli / genetics*
  • Gene Expression Regulation, Bacterial*
  • Models, Genetic
  • Molecular Sequence Data
  • Mutagenesis
  • Osmolar Concentration
  • Phosphorylation
  • Porins
  • Promoter Regions, Genetic / genetics
  • Sequence Homology, Amino Acid
  • Signal Transduction
  • Structure-Activity Relationship
  • Transcription, Genetic*


  • Bacterial Outer Membrane Proteins
  • DNA-Binding Proteins
  • Porins