多重耐药及泛耐药鲍曼不动杆菌外排泵基因adeB的研究

RESEARCH ABOUT EFFLUX PUMP GENE adeB IN MULTIDRUG RESISTANCE AND PANDRUG RESISTANT ACINETOBACTER BAVMANNII

目的观察多重耐药及泛耐药鲍曼不动杆菌主动外排泵在耐药方面的作用和外排泵基因表达情况。方法通过比较加入羰基氰氯苯(carbonyl cyanldem-chlorophenyl hydrazone,CCCP)泵抑制剂前后96株鲍曼不动杆菌对四环素、诺氟沙星、庆大霉素、头孢噻肟4种药物最小抑菌浓度(minimum inhibitory concentration,MIC)的变化,筛选出34株外排泵表型阳性的鲍曼不动杆菌。用聚合酶链反应扩增对34株菌进行外排泵蛋白基因adeB的检测和分析,并测序。结果最终筛选出对4种抗生素MIC值均降低4倍及以上菌34株(35.42%),34株外排泵表型阳性的鲍曼不动杆菌检测到adeB基因33株,检出阳性率为97.06%。对33株鲍曼不动杆菌的外排泵基因adeB进行测序,经比对所测序列与基因库(Genebank)中序列同源性为100.00%。结论泵抑制剂CCCP对于逆转鲍曼不动杆菌对四环素、诺氟沙星、庆大霉素、头孢噻肟4种抗菌药物的耐药性起到重要作用,主动外排泵基因是鲍曼不动杆菌发生多重耐药的重要因素。

Objective To investigate efflux pump drug-resistance and gene expression in multidrug resistant and pandrug resistant Acinetobacter baumannii.Methods The multidrug resistant Acinetobacter baumannii efflux pump phenotypes were detected by joining carbonyl cyanidem-chloropheny hydrazone （CCCP）pump inhibitors,the minimum inhibitory concentration （MIC）variation was observed in 9 6 strains of Acinetobacter baumannii resistant to tetracycline, norfloxacin,gentamicin,cefotaxime,34 strains of efflux phenotype positive Acinetobacter baumannii were screened out.The efflux pump protein gene adeB in 34 Acinetobacter baumannii were detected and sequenced with the polymerase chain reaction amplification.Results The initial selection involoed 34 strains （35.42%）whose MIC reduced by 4 times and above.In 34 stains of efflux pump phenotype positive Acinetobacter baumannii,33 strains were detected adeB gene,the positive rate was 97.06%.When the 33 strains Aacinetobacter baumannii adeB efflux pump gene were sequenced,the sequence homology was 100.00% compared in Genebank.Conclusion Pump inhibitor CCCP plays an important role in the reversal of Acinetobacter baumannii resistant to tetracycline,norfloxacin,gentamicin and cefotaxime,active efflux pump genes play an important role in multidrug resistant Acinetobacter baumannii.