耐碳青霉烯类鲍曼不动杆菌外排泵AdeABC的研究  

Role of the AdeABC efflux pump in carbapenems resistance of clinical isolates of Acinetobacter baumannii

作　　者：马真[1] 蔡绍曦[2] 佟万成[2] 阮世冲[2] 王辉[1] 

机构地区：[1]深圳市龙岗中心医院呼吸内科,广东深圳518116 [2]南方医科大学南方医院呼吸内科,广东广州510515

出　　处：《南方医科大学学报》2011年第8期1378-1381,共4页Journal of Southern Medical University

基　　金：广东省科技计划项目(2008A060202013)

摘　　要：目的从外排泵表型和基因型两个方面探讨外排泵系统在鲍曼不动杆菌对碳青霉烯类抗生素耐药机制中所起的作用。方法外排泵抑制剂羰基氰氯苯腙(CCCP)对138株鲍曼不动杆菌的外排泵进行表型检测;荧光定量PCR测定外排泵adeABC在51株鲍曼不动杆菌中的表达情况。结果泵抑制剂羰基氰氯苯腙(CCCP)和美罗培南协同实验的结果显示:138株临床分离菌中,CCCP抑制实验共筛选出泵阳性菌株28株,其中对美罗培南耐药的39株菌中有15株即38.4%的菌株为泵阳性株,对美罗培南敏感的99株菌中有13株即13.1%的菌株为泵阳性株。经卡方检验统计学分析,差异有显著意义(χ2=12.477b,P=0.01);荧光定量PCR检测菌株的adeB和16s rRNA后,根据检测结果计算出adeB表达量差异。经t检验统计学分析结果显示碳青霉烯类抗生素敏感组的adeB的表达量是0.899±1.172,耐药组的表达量是21.101±21.443,敏感组的表达量显著低于耐药组的表达量,差异有统计学意义(t=4.403,P=0.000)。结论主动外排泵机制在临床分离的鲍曼不动杆菌对碳青霉烯类抗生素的耐药机制中起作用。adeB基因或者adeABC外排泵机制可能在临床菌株对碳青霉烯类抗生素的耐药机制中起作用。Objective To investigate the role of AdeABC efflux pump in carbapenems resistance of Acinetobacter baumannii in light of the phenotype and genetype of the efflux pump.Methods The phenotype of the efflux pump was detected in 138 clinical isolates of A.baumannii using the efflux pump inhibitor carbonyl cyanide 3-chlorophenylhydrazone（CCCP）.The mRNA expression of pump-encoding gene adeB in the strains was detected using quantitative real-time RT-PCR.Results Of the 138 strains,28 showed positivities for AdeABC efflux pump identified by Mueller-Hinton Broth with CCCP.Of the 39 strains resistant to meropenem,15（38.4%） showed positive results in CCCP assay,a rate significantly higher than that among the 99 sensitive strains（13.1%,13/99）（χ2=12.477b,P=0.01）.The mRNA expression of efflux pump-encoding gene adeB was detected by real-time RT-PCR at a level of 0.899±1.172 in meropenem-sensitive strains,significantly lower than the level of 21.101±21.443 in meropenem-resistant strains（t=4.403,P=0.000）.Conclusion Efflux plays a role in carbapenems resistance in the clinical isolates of A.baumannii.The AdeABC efflux pump may be an important factor in reducing carbapenems sensitivity in A.baumannii.

关 键 词：鲍曼不动杆菌 外排泵 碳青酶烯类 实时定量PCR 

分 类 号：R378[医药卫生—病原生物学]