猪源化脓隐秘杆菌分离的鉴定与病原特性研究

Isolation and Identifi cation of Arcanobacterium pyogenes of Swine Origin and Pathogenicity in Mice

从天津地区某猪场病猪肺脏脓肿中分离到一株具有β溶血特性的细菌,经形态学与生化特性分析,初步确定为化脓隐秘杆菌(Arcanobacterium pyogenes),并命名为TJjh1913。利用PCR扩增16S rRNA基因,经Blast序列分析,其序列与GenBank数据库中猪源化脓隐秘杆菌的核苷酸序列同源性高达99.9%,证实该分离株为猪化脓隐秘杆菌;该菌携带Plo、NanH、CbpA 3种毒力基因,动物实验表现出较强致病性,昆明系小鼠LD50为105 CFU;药敏试验结果显示,该菌对头孢类及喹诺酮类药物高度敏感,对氨基糖苷类药物耐药。本研究结果为猪化脓隐秘杆菌的鉴定及其流行病学调查与防治提供了参考依据。

One bacterial strain TJjh1913 withβhemolytic activity was isolated from lung abscess of a pig in Tianjin area and identifi ed as Arcanobacterium pyogenes by morphological and biochemical analyses.Then the 16S rRNA genes were amplifi ed by PCR and sequence was analyzed by Blast software.The result showed that the 16S rRNA sequence of TJjh1913 strain was 99.9%homologous with that of Arcanobacterium pyogenes in published GenBank.Further analysis revealed that it carried 3 virulence genes Plo,NanH and CbpA.In addition,the bacterial culture was inoculated into Kunming mice for testing its pathogenicity and LD50 dose was determined to be 105 CFU/mL.Drug susceptibility testing indicated that this strain was highly sensitive to cephalosporins and fluoroquinolones and resistant to aminoglycoside.These results provided useful information on identifi cation,epidemiological investigation and control of porcine A.pyogenes.