鲍曼不动杆菌环丙沙星耐药性接合转移的实验研究

Experimental Study on Conjugation Transfer of Ciprofloxacin Resistance in Acinetobacter baumanii

目的:探讨质粒转移与鲍曼不动杆菌环丙沙星(CIP)耐药性的关系。方法:将鲍曼不动杆菌CIP耐药菌株(供体菌)与E.coli(C600SMRLac-)(受体菌)进行接合试验,采用琼脂稀释法测定供体菌及接合子的CIPMIC值。结果:16株CIP耐药性鲍曼不动杆菌,其中5株CIP耐药株与受体菌成功发生了接合,CIP耐药性接合转移的发生率为31.25%(5/16)。接合子的CIPMIC值比受体菌增加了30～500倍,其中1株接合子对CIP呈现低水平耐药。结论:部分鲍曼不动杆菌的CIP耐药性与质粒有关,且能够通过接合方式在细菌之间发生转移。

Objective： To investigate the relationship between plasmid transfer and ciprofloxacin resistance in A.baumanii. Methods： The conjugation experiments were carried out with ciprofloxacin-resistant A.baumanii as donor strains and E.coli （C600 SMR Lac ） as the recipient, and MICs for the donor, recipient, and transconjugant strains were measured by agar dilution. Results： Five strains of ciprofloxacin-resistant A. baumanii were conjugated with the recipient, and the incidence rate of conjugation transfer of ciprofloxacin resistance was 31.25%（5/16）. Ciprofloxacin MICs for the transconjugant strains increased by 30 to 500 times than that of the recipient sWain, and one strain of the transconjugant was low-level ciprofloxacin resistance. Conclusion： In some isolates of A. baumanii, the ciprofioxacin resistance is realted to the plasmid, and can be transferred to other bacteria by conjugation.