山羊源奥斯陆莫拉菌的分子鉴定与分析

目的 对重庆市某羊场送检的山羊肺炎病例进行病原菌分离培养,从分子水平上对该病原菌进行分类学鉴定与分析。方法 分离纯化病原菌后,进行形态学鉴定,药敏试验和致病性试验,并采用细菌通用引物扩增该病原菌的16SrDNA,对扩增的核苷酸序列进行测序和分析。结果 所得病原菌为革兰氏阴性杆菌,对多种抗生素敏感,能够引起健康羊只出现呼吸道疾病,PCR扩增出长约1 447 bp的目的片段,将该序列与NCBI中已公布的序列进行比对,发现所得序列与奥斯陆莫拉菌(Moraxella osloensis,登陆编号为JN084136)同源性高达99.9％。并将该序列与其相关性较高的奈瑟氏菌属(Neisseria)、莫拉克斯氏菌属(Moraxella)、俊片菌属(Lampropedia)与副球菌属(Paracoccus )等4种菌属的代表菌株16S rDNA构建系统发育进化树,结果显示该病原菌与莫拉克斯氏菌属(Moraxella)聚为一簇。结论 研究表明,从山羊肺炎病例分离到的菌株为奥斯陆莫拉菌。

Molecular classification and analysis of Moraxella osloensis from goats

The pathogenic bacterium was evaluated according to the system analysis at the molecular level, which was acquired from the goat suspected of suffering from pneumonia in a field in Wushan County. The pathogenic bacterium was stud- ied by means of morphological identification, drug sensitive test, and pathogenicity test after the separation and purification. Then the 16SrDNA was amplified, sequenced and analyzed using universal primers from the pathogenic bacteria. Result showed that the isolated strain was gram-negative and sensitive to many antibiotics, causing the respiratory disease of the goat. A se- quence of 1 447 base pairs was obtained from the bacteria. Sequence compared to these derived from GenBank using BLASTn, and the closest sequence was the 16S rDNA gene of Moraxella osloensis strain, with a similarity of 99.9%, which was regis- tered as JN084136. The pathogenic bacteria formed a separate with Moraxella according to the system development of the evo- lutionary tree that was based on the 16S rDNA genes sequences of the pathogenic bacteria and other related organisms, inclu- ding the represent strain of Neisseria, Moraxella, Lampropedia, and Paracoccus. The investigation manifested that the path- ogenic bacterium is Moraxella osloensis.