[Comparison of the transcriptional levels of mannitol PTS operon between epidemic and non-epidemic strains of Vibrio cholerae].
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.
Wang
Hai-Yan
HY
Department of Microbiology, Medical College, Soochow University, Suzhou, Jiangsu 215123, China.
Zheng
Xiao
X
Lou
Jing
J
Yan
Mei-Ying
MY
Zhao
Ying-Wei
YW
Kan
Biao
B