氨基糖苷类药物高水平耐药16S rRNA甲基化酶基因在动物源大肠杆菌中的检测

Detection of 16S rRNA Methylase Genes Which Mediated High Level Resistance to Aminoglycosides among Escherichia coli Strains Isolated from Animals

为了解郑州地区氨基糖苷类药物高水平耐药16S rRNA甲基化酶基因(armA、rmtA、rmtB、rmtC、rmtD和npmA)在健康动物大肠杆菌中的流行情况,对2009年在郑州地区鸡、犬、猪的肛门拭子中分离保存的231株大肠杆菌进行了药敏试验,并分别设计特异性引物对其进行16S rRNA甲基化酶基因的聚合酶链式反应扩增。结果显示:在6种基因中,鸡、犬源大肠杆菌可检测到armA和rmtB,而猪源大肠杆菌仅检测出rmtB。鸡、犬源大肠杆菌armA的检测率分别为7.6%和3.3%;鸡、犬、猪源大肠杆菌rmtB的检出率分别为47.8%、20.0%和0.9%。其中,鸡、犬中分别有3.3%的大肠杆菌可同时检测到armA和rmtB。

The epidemiology of 16S rRNA methylase genes （armA, rmtA, rmtB, rrntC, rrntD and npmA） which mediated the high level resistance to aminoglycosides among Escherichia coli strains isolated from animals in Zhengzhou was investigated. Two hundred and thirty - one Escherichia coli strains were isolated from chickens, pigs and dogs in 2009. Antibacterial susceptibility determinations were performed and six types of 16S rRNA methylase genes were detected by PCR. The results indicated that among six types of 16S rRNA methylase genes, armA and rmtB were detected in Escherichia coli strains isolated from chickens and dogs, while only rmtB was detected in Escherichia coli strains isolated from pigs. The positive rates of armA among these Escherichia coli strains in chickens and dogs were 7.6% and 3.3%, respectively, while those of rmtB among these E. coli strains in chickens, dogs and pigs were 47.8%, 20. 0% and 0. 9%, respectively. The concurrence rates of arrrtA and rmtB in E. coli strains in chickens and dogs were both 3.3%. This suggested that the positive rate of 16S rRNA methylase genes among E. coli strains isolated from chickens was relatively higher in Zhengzhou, the gene rrntB was dominant among six genes.