3株牛布鲁氏菌19疫苗株赤藓醇代谢基因的克隆与序列分析

Sequence Analysis on Erythritol catabolic genes of 3 Different B.abortus strain 19

对3株(国际标准参考株S19,中国天康疫苗株A19-1,中国中监所标准株A19-2)不同来源布鲁氏菌19疫苗株的赤藓醇代谢基因(Erythritol catabolic gene,简写Ery)进行克隆与序列分析。参照GenBank中布鲁氏菌牛种2308的赤藓醇代谢基因序列,设计一对特异性引物,用PCR方法扩增3株19疫苗株Ery基因,对PCR产物进行克隆、测序分析。与2308比较,S19的Ery基因缺失702碱基,两株中国来源的A19不缺失,但阅读框的51,52位CG变为GC,521,522,523缺失AGG,547位T变为C。引起的氨基酸变化有,13位R变为A,170位T变为A,178位V变为A。赤藓醇代谢基因的克隆测序结果表明,我国的两株A19均不缺失702个碱基,但有3处发生点突变,引起3个氨基酸发生变化。

Sequence analysis was conoducted on erythritol catabolic genes of 3 different 13. abortus strain 19. A pair of primers were designesd for amplification of brucella erythritol catabolic genes according to the complete genomic sequence of Brucella abortus 2308 in GenBank. Erythritol catabolic genes were amplified from 3 different B. abortus strain 19 by polymerase chain reaction （PCR）. The PCR products were cloned in pMD18-T vector for sequencing. Results Sequence analysis showed that the reference strains was absent on 702bp,and 2 of Chinese strains were not absent,compared with 2308 strain. But in the sequence 51th, 52th,CG become GC;at 521th,522th,523th,AGG was absent;at 547th,T becomes C. causes 3 aminophenol change：at 13th,R becomes A;at 170 th,T become A;at 178 th,V becomes A. Sequence analysis on erythritol catabolic genes showed that 2 of Chinese strains had 3 spots changed, caused 3 aminophenol change.