霍乱弧菌中环腺苷酸受体蛋白对高丝氨酸脱氢酶基因的调控作用

摘要

Objective: To elucidate the effect of cAMP receptor protein(CRP) on the transcription of homoserine dehydrogenase(HDH) in Vibrio cholerae. Methods: Using overlap PCR, the possible CRP bingding site in the pro-moter of HDH gene was replaced by consensus sequence. The transcriptional reporter plasmids containing the origi-nal promoter or changed promoter were constructed, and these plasmids were introduced into the V.cholerae C7258 and CRP mutant strain WL7258 by conjugation. The transcription level was compared by monitoring luminescence value in C7258 and WL7258. Results: Our data showed that luminescence value of plasmid which containing the original promoter was higher in C7258 than WL7258. After the promoter was changed, luminescence value of plas-mid were raised in two strains, especially in C7258. Conclusion: The results demonstrated that CRP regulates the transcription of HDH in V.cholerae, but CRP was not the only regulation factor.%目的：研究霍乱弧菌中环腺苷酸受体蛋白（CRP)对高丝氨酸脱氢酶（HDH）是否具有调控作用。方法：通过搭桥PCR将HDH基因启动子中CRP潜在结合位点替换为CRP保守结合位点，分别将替换前后的启动子序列导入报告质粒，转化霍乱弧菌野生株C7258及CRP缺失株WL7258，比较荧光值的差异。结果：改造前报告质粒在野生株中的荧光值高于CRP缺失株，改造后报告质粒的荧光值在2株菌中均有升高，但在野生株中升高更明显。结论：CRP调控HDH的转录，但不是惟一调控因素。