丝状支原体丝状亚种SC型中国不同地区分离株脂蛋白Q基因的分子特征  

Molecular characterization of the lipoprotein Q gene of Mycoplasma mycoide subsp. mycoides SC isolated from China

作　　者：高玉龙[1] 辛九庆[1] 李媛[1] 王砚范[1] 

机构地区：[1]中国农业科学院哈尔滨兽医研究所国家牛传染性胸膜肺炎参考实验室,黑龙江哈尔滨150001

出　　处：《中国预防兽医学报》2006年第2期142-146,共5页Chinese Journal of Preventive Veterinary Medicine

基　　金：国家"十五"科技攻关重大专项资助项目(2002BA518A04)

摘　　要：根据已发表的丝状支原体丝状亚种SC型(MmmSC)脂蛋白Q(LppQ)基因序列设计并合成一对引物,利用PCR扩增方法,从我国不同省区的MmmSC分离株HVRI-Ⅹ、BenⅠ、QingⅠ、MuⅠ和模式株PG1中获得了LppQ基因1303bp的片段,将该片段克隆到PMD18-T载体上,通过对所得到的重组质粒进行酶切分析、PCR鉴定,证明得到了含有目的基因片段的阳性重组质粒。采用Sanger's双脱氧末端终止法对插入片段进行核苷酸序列测定,获得了HVRI-Ⅹ、BenⅠ、QingⅠ、MuⅠ株和模式株PG1LppQ基因核苷酸序列。核苷酸序列比较结果显示,国内4个MmmSC分离株与GenBank公布的LppQ基因核苷酸序列同源性均在99.7%以上,氨基酸序列同源性均在99%以上;与模式株PG1的核苷酸序列同源性在99.7%以上,氨基酸序列同源性均在99.3%以上。国内4个MmmSC分离株之间的核苷酸序列同源性均在99.7%以上,氨基酸序列同源性均在99.3%以上。对HVRIⅩ株LppQ基因氨基酸亲水性和蛋白表面可能性进行了分析,证实LppQN末端富含亲水氨基酸,比C末端更有可能定位在蛋白表面。The lipoprotein Q （LppQ） gene was amplified from MmmSC HVRI-X, Ben Ⅰ, Qing Ⅰ, Mu Ⅰ strain and type strain PG1 by PCR using the primer pair designed according to the reported MmmSC LppQ gene sequence. They were cloned and sequenced subsequenlly. Comparative analysis of these LppQ gene sequences showed that MmmSC HVRI-X, Ben Ⅰ , Qing Ⅰ , Mu I strain shared 99.7 % identity in nucleotide sequence with foreign MmmSC strain and type strain PG1, and shared 99.0 % identical in induced amino acid sequence with them. There was 99.7 % identity in nucleotide sequence between MmmSC HVRI-X , Ben Ⅰ , Qing Ⅰ , Mu Ⅰ strain and 99.3 % identical in induced amino acid sequence between them. Analysis of hydrophilic prediction and surface probability of MmmSC HVRI-X LppQ showed that the N-terminal domain was surface exposed and rich in hydrophilic amino acid.

关 键 词：牛传染性胸膜肺炎 丝状史原体丝状亚种SC型 脂蛋白 LppQ 分子特征 

分 类 号：S858.26[农业科学—临床兽医学] Q78[农业科学—兽医学]