N9L and L9N mutations toggle Hha binding and hemolysin regulation by Escherichia coli and Vibrio cholerae H-NS.
Proteins of the Hha/YmoA family co-regulate with H-NS the expression of virulence factors in Enterobacteriaceae. Vibrio cholerae lacks Hha-like proteins and its H-NS (vcH-NS) is unable to bind Hha, in spite of the conservation of a key residue for Hha binding by Escherichia coli H-NS (ecH-NS). Exchange of the residues in position 9 between vcH-NS and ecH-NS strongly reduces Hha binding by ecH-NS and introduces it in vcH-NS. These mutations strongly affect the repression of the hemolysin operon in E. coli and the electrophoretic mobility of complexes formed with a DNA fragment containing its regulatory region.
García
Jesús
J
Institute for Research in Biomedicine, Parc Científic de Barcelona, Barcelona, Spain.
Madrid
Cristina
C
Cendra
Mar
M
Juárez
Antonio
A
Pons
Miquel
M
D000595:Amino Acid Sequence; D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism*; D004268:DNA-Binding Proteins / Q000235:genetics / Q000378:metabolism*; D004926:Escherichia coli / Q000235:genetics* / Q000378:metabolism* / Q000472:pathogenicity; D029968:Escherichia coli Proteins / Q000235:genetics / Q000378:metabolism*; D015964:Gene Expression Regulation, Bacterial; D006460:Hemolysin Proteins / Q000235:genetics / Q000378:metabolism*; D008969:Molecular Sequence Data; D009154:Mutation; D019906:Nuclear Magnetic Resonance, Biomolecular; D009876:Operon; D011485:Protein Binding; D016415:Sequence Alignment; D014734:Vibrio cholerae / Q000235:genetics* / Q000378:metabolism* / Q000472:pathogenicity
D001426:Bacterial Proteins; D004268:DNA-Binding Proteins; D029968:Escherichia coli Proteins; C031908:H-NS protein, bacteria; D006460:Hemolysin Proteins; C079209:hha protein, E coli