霍乱弧菌双精氨酸转运系统基因共转录和同源性分析  

Analysis of twin-arginine translocation system gene homology and transcription in Vibrio species

作　　者：朱召芹[1] 陈海丽[1] 周海健[3] 景怀琦[3] 闫梅英[3] 宰淑蓓[2] 蔡金凤[2] 胡芸文[1] 阚飙 

机构地区：[1]上海市公共卫生临床中心病原体应急检测与生物安全部,201508 [2]上海市公共卫生临床中心医学检验科,201508 [3]中国疾病预防控制中心传染病预防控制所

出　　处：《中华预防医学杂志》2015年第2期116-121,共6页Chinese Journal of Preventive Medicine

基　　金：国家“十二五”科技重大专项（2012ZX10004-221、2013ZX10004221-004）;国家自然科学基金青年基金（31200108）;上海市卫生局青年基金（20124467）;2013年上海市公共卫生临床中心启动基金

摘　　要：目的研究霍乱弧菌双精氨酸转运系统（twin—arginine translocation system，Tat）基因簇各个基因的共转录情况，并确定参与Tat转录基因簇构成。方法选择霍乱弧菌埃尔托生物型菌株N16961和tatABC基因缺失株N169-dtat进行Tat基因簇及上下游基因，即上游蛋白质生物合成ubi aarF基因和下游细胞色素C551过氧化物酶编码基因咧551基因进行逆转录，分析Tat基因簇的共转录情况。选择霍乱弧菌及其他弧菌属菌株，通过PCR产物测序和序列比对，对Tat转运系统的同源性进行比较，进行Tat基因簇各基因聚类分析。结果Tat基因簇4个基因（tatA、tatB、tatC和ratE）均可以共转录。ubi aarF基因可以与tatA及tatB共转录。cyt551基因与上游的4个基因均不共转录；通过N16961 Tat基因缺失株总RNA逆转录分析发现，虽然ubi aarF与tatA、tatB的共转录由于基因缺失被阻断，但该基因仍可以被分别转录。不同型别的霍乱弧菌和其他弧菌属的菌株tarA、tatB、tatC、ratE单基因和tatABC基因簇聚类分析结果表明，Tat基因簇的种属变异性很小，是一段很保守的序列。结论霍乱弧菌ubi aarF基因与Tat基因簇可能共同受调控因子的作用；Tat基因在弧菌属中属于保守结构。Objective To determine the function of twin-arginine translocation system （Tat） and gene cluster in Vibrio strains and to analyze the homology of tat gene cluster among different Vibrio spp. strains based on N16961 and tatABC mutant strains N169-dtat. Methods Different serotypes of biotype strains of Vibrio spp. were selected to detect the transcription of 4 genes of Tat transport system and upstream ubi aarF gene and downstream cyt551 gene by the total RNA reverse transcription and homologieity of the gene cluster by sequencing analysis. Results Our results showed that the 4 genes of tat cluster （ tatA, tatB, tatC, and tatE） were intragenie and co-transcribed. We found that ubi aarF gene could be co-transcribed with ratA, tatB, hut not with tatC. The electron transport chain and energy metabolism-related genes, cytochrome C551 peroxidase gene, and 4 genes located at upstream of tatABC operon were not transcribed with tatABC. Akhough the co-transcription between ubi aarF and tatAB was blocked in N169-dtat strain, they were still transcribed separately. Homologous analysis of genes of tat cluster in different types of Vibrio cholerae showed that tat gene cluster was a very conservative. Conclusion The ubi and aarF gene might be co-transcribed with genes of tat cluster in Vibrio cholerae, which and the close relationship showed that they might play a key function in Vibrio cholerae.

关 键 词：弧菌 霍乱 基因 序列同源性 

分 类 号：R378.3[医药卫生—病原生物学]