A role for H-NS in the thermo-osmotic regulation of virulence gene expression in Shigella flexneri.
The role of the hns gene (coding for the curved-DNA-binding protein H-NS) in the thermo-osmotic regulation of Shigella flexneri virulence gene transcription was investigated. Two structural genes, mxiC and icsB, which are transcribed divergently on the high-molecular-weight virulence plasmid, were found to be transcriptionally inhibited in cultures grown in a low-osmolarity medium, even at the inducing temperature. This repression was relieved by inactivation of the hns gene, establishing a role for hns in the osmotic as well as the thermal regulation of invasion gene expression. The physiological relevance of this finding is discussed.
Porter
M E
ME
Department of Biochemistry, University of Dundee, Scotland, United Kingdom.
Dorman
C J
CJ
D001425:Bacterial Outer Membrane Proteins / Q000235:genetics / Q000378:metabolism*; D001426:Bacterial Proteins; D001483:Base Sequence; D004268:DNA-Binding Proteins / Q000235:genetics / Q000378:metabolism*; D015964:Gene Expression Regulation, Bacterial; D005798:Genes, Bacterial / Q000235:genetics; D006358:Hot Temperature; D008969:Molecular Sequence Data; D009997:Osmotic Pressure; D012763:Shigella flexneri / Q000235:genetics* / Q000472:pathogenicity*; D015398:Signal Transduction; D014158:Transcription, Genetic; D014774:Virulence / Q000235:genetics
D001425:Bacterial Outer Membrane Proteins; D001426:Bacterial Proteins; D004268:DNA-Binding Proteins; C031908:H-NS protein, bacteria