[Transcriptional repressor gene--mtlR of mannitol PTS operon in Vibrio cholerae].
The fermentation rates of mannitol in toxigenic and non-toxigenic El Tor strains of Vibrio cholerae are obviously different, which is a valuable indicator in the rapid identification of toxigenic strain. To determine the regulating role of mtlR in transcription of mannitol PTS operon in V. cholerae, and whether it plays a role in the ferment difference of the toxigenic and non-toxigenic strains, the mtlR deletion mutants from the mannitol rapid-ferment strain (non-toxigenic strain) and slow-ferment strain (toxigenic strain) were constructed. Comparisons of the growth in M9 containing 0.2% mannitol as the sole carbon source and pH change in mannitol fermentation media of these wild strains and their mutants, indicated that mtlR is a repressor. Its repression in mtlCBA transcription was further verified with the analyses of quantitative reverse-transcriptional PCR. However, the regulation of mtlR is not the immediate cause of the ferment difference of the toxigenic and non-toxigenic strains. The study also provides the necessary data in the analyses of mannitol ferment difference between the toxigenic and non-toxigenic V. cholerae strains.
Wang
Hai-yan
HY
Department of Microbiology, Medical College, Soochow University, Suzhou 215123, China. wanghaiyan-cdc@163.com
Yan
Mei-ying
MY
Zhao
Ying-wei
YW
Kan
Biao
B
D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism*; D015964:Gene Expression Regulation, Bacterial; D008353:Mannitol / Q000378:metabolism*; D009876:Operon; D010731:Phosphoenolpyruvate Sugar Phosphotransferase System / Q000235:genetics* / Q000378:metabolism; D012097:Repressor Proteins / Q000235:genetics / Q000378:metabolism*; D014158:Transcription, Genetic; D014734:Vibrio cholerae / Q000235:genetics* / Q000378:metabolism
D001426:Bacterial Proteins; D012097:Repressor Proteins; D008353:Mannitol; D010731:Phosphoenolpyruvate Sugar Phosphotransferase System