Expression and mutational analysis of the nucleoid-associated protein H-NS of Salmonella typhimurium

Mol Microbiol. 1992 Aug;6(16):2327-37. doi: 10.1111/j.1365-2958.1992.tb01408.x.


The H-NS (H1) protein is a major component of bacterial chromatin. Mutations in the hns (osmZ) gene encoding H-NS are highly pleiotropic, affecting the expression of many unrelated genes in an allele-specific manner. H-NS expression was found not to vary with growth phase or growth medium osmolarity. Additionally, 10 independent hns mutations were isolated and characterized. Five of these mutations were the result of an IS10 insertion, each generating a truncated polypeptide. The other five mutations were the same specific deletion of one amino acid, delta Ala46. The various hns mutations exhibited different phenotypes and influenced DNA topology to variable extents. Implications for the mechanism by which H-NS influences gene expression are discussed.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Bacterial Outer Membrane Proteins / genetics*
  • Bacterial Outer Membrane Proteins / metabolism
  • Bacterial Proteins*
  • Base Sequence
  • Blotting, Western
  • DNA, Bacterial / genetics
  • DNA, Superhelical / genetics
  • DNA-Binding Proteins / genetics*
  • DNA-Binding Proteins / metabolism
  • Electrophoresis, Gel, Two-Dimensional
  • Gene Expression Regulation, Bacterial
  • Kinetics
  • Molecular Sequence Data
  • Mutation
  • Peptides / genetics
  • Phenotype
  • Salmonella typhimurium / genetics*
  • Salmonella typhimurium / isolation & purification
  • Salmonella typhimurium / metabolism


  • Bacterial Outer Membrane Proteins
  • Bacterial Proteins
  • DNA, Bacterial
  • DNA, Superhelical
  • DNA-Binding Proteins
  • H-NS protein, bacteria
  • Peptides