title: [Comparison of the transcriptional levels of mannitol PTS operon between epidemic and non-epidemic strains of Vibrio cholerae].
abstract: OBJECTIVE
  To compare the transcription difference of the mannitol PTS genes between epidemic and non-epidemic strains of Vibrio cholerae El Tor in mannitol ferment tests.
  
  
  METHODS
  Growth curves of 10 epidemic strains (slow-ferment) and 10 non-epidemic strains (rapid-ferment) of Vibrio cholerae were detected in the process of fermentation test, and the transcriptional level of mannitol PTS operon of these strains were determined with quantitative reverse-transcriptional PCR.
  
  
  RESULTS
  After 4 hours of test, the non-epidemic strains became positive and the average growth density of the non-epidemic strains was higher than that of the epidemic strains; however, some were still lower than the epidemic strains. In contrast, at the eighth hour of test, when epidemic strains got positive, they showed higher average growth density. Compared to the epidemic strains, the transcription of mannitol PTS genes of the non-epidemic strains were much more active at the 1st and 2nd hour and were lower at the 4th and 8th hour.
  
  
  CONCLUSIONS
  The difference of mannitol PTS operon transcription level should be an important feature to identify the epidemic and non-epidemic strains of Vibrio cholerae, which directly influences the mannitol fermentation rate during the test. The growth rate is not a key factor that affect such difference.
authors.affiliation: Department of Microbiology, Medical College, Soochow University, Suzhou, Jiangsu 215123, China.
authors.forename: Hai-Yan
authors.initials: HY
authors.lastname: Wang
authors.forename: Xiao
authors.initials: X
authors.lastname: Zheng
authors.forename: Jing
authors.initials: J
authors.lastname: Lou
authors.forename: Mei-Ying
authors.initials: MY
authors.lastname: Yan
authors.forename: Ying-Wei
authors.initials: YW
authors.lastname: Zhao
authors.forename: Biao
authors.initials: B
authors.lastname: Kan