Expression of Salmonella typhi and Escherichia coli OmpC is influenced differently by medium osmolarity; dependence on Escherichia coli OmpR

Mol Microbiol. 1991 May;5(5):1205-10. doi: 10.1111/j.1365-2958.1991.tb01894.x.


OmpC, a major outer-membrane protein, is highly expressed when Salmonella typhi is grown in nutrient broth (NB) of either low (NB + 0% sucrose) or high (NB + 20% sucrose) osmolarity. This contrasts with the expression of Escherichia coli OmpC, which is inhibited in low osmolarity and enhanced in high osmolarity, as has been described previously (van Alphen and Lugtenberg, 1977; Verhoef et al., 1979; Kawaji et al., 1979). Nevertheless, expression of S. typhi OmpC is dependent on the E. coli OmpR transcriptional activator. These findings suggest differences between the mechanisms of osmoregulation of gene expression in both bacteria, although common effectors appear to be shared.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Bacterial Outer Membrane Proteins / biosynthesis*
  • Bacterial Outer Membrane Proteins / genetics
  • Bacterial Outer Membrane Proteins / metabolism*
  • Culture Media / pharmacology
  • Escherichia coli / genetics*
  • Escherichia coli / metabolism
  • Escherichia coli Proteins*
  • Gene Expression Regulation, Bacterial* / drug effects
  • Multienzyme Complexes*
  • Osmolar Concentration
  • Recombinant Fusion Proteins / metabolism
  • Salmonella typhi / genetics*
  • Salmonella typhi / metabolism
  • Signal Transduction
  • Transcription, Genetic


  • Bacterial Outer Membrane Proteins
  • Culture Media
  • Escherichia coli Proteins
  • Multienzyme Complexes
  • Recombinant Fusion Proteins
  • envZ protein, E coli