鲍曼不动杆菌16SrRNA甲基化酶基因和氨基糖苷类修饰酶基因检测及作用研究

目的了解医院分离的多重耐药的鲍曼不动杆菌（ABA）氨基糖苷类药物各种耐药相关基因存在状况,探讨ABA多药耐药机制。方法收集20株分离自2010年1-12月岳阳市二人民医院患者临床分离的ABA,采用纸片扩散法测定16种抗菌药物的敏感性,采用PCR法检测armA、rmtA、rmtBr、mtC、rmtD、npmAa、ac（3）-Ⅰa、ac（3）-Ⅱ、aac（6′）-Ⅱ、aac（6′）-Ⅰba、ac（6′）-Ⅰa、ant（3＂）-Ⅰ、ant（2＂）-Ⅰ等16SrRNA甲基化酶与氨基糖苷类修饰酶基因。结果 1株检出16SrRNA甲基化酶基因（armA）,15株检出氨基糖苷类修饰酶基因其中aac（3）-Ⅰ为80%、ant（2＂）-Ⅰ为80%、aac（3）-Ⅱ为40%、aac（6′）-Ⅰb为15%]。结论鲍曼不动杆菌的多重耐药与氨基糖苷类修饰酶基因和16-SrRNA甲基化酶基因相关。鲍曼不动杆菌存在新的氨基糖苷类药物耐药机制。

Study on the Genes of 16srRNA Methylase and Aminoglycoside Modifying Enzymes in Acinetobacter baumannii

Objective To investigate the resistant genes against aminoglycoside antibiotics in multi-drug-resistant Acinetobacter baumannii isolated inthe Second People’s Hospital of Yueyang and explore its mechanism of multi-drug resistance.Methods 20 strains of Acinetobacter baumannii from patients visiting our hospital in 2010 were collected.Their sensitivity to 16 antibiotics was determined by disc diffusion method.Aminoglycoside-modifying enzyme genes(aac(3)-Ⅰ,aac(3)-Ⅱ,aac(6′)-Ⅱ,aac(6′)-Ⅰb,aac(6′)-Ⅰa,ant(3")-Ⅰ,ant(2")-Ⅰ) and 16srRNA methylase genes(armA,rmtA,rmtB,rmtC,rmtD,npmA) were detected by polymerase chain reaction(PCR).Results One strain of Acinetobacter baumannii carried 16srRNA methylase gene armA,and 15 strains carried aminoglycoside-modifying enzyme genes,80% with aac(3)-Ⅰ,80% with ant(2")-Ⅰ,40% with aac(3)-Ⅱ and 15% with aac(6′)-Ⅰb.Conclusions The multi-drug resistance of Acinetobacter baumannii is closely related with 16srRNA methylase and aminocoside-modifying enzyme genes.It has new aminoglycoside-resistance mechanisms.