致血液系统感染大肠埃希菌中I类整合子参与耐药的研究

THE STUDY ON CLASS 1 INTEGRONS IN MEDIATION OF ANTIBIOTIC RESISTANCE IN ISOLATES OF ESCHERICHIA COLI FROM BLOOD INFECTION.

目的:探讨致血液系统感染大肠埃希菌中I类整合子介导耐药性的分子机制。方法:应用全自动细菌分析仪Microscan WalkAway40和纸片扩散法,对16株大肠埃希菌进行抗生素敏感性测定,PCR扩增细菌总DNA上的I类整合子,对扩增产物测序并分析其中的基因盒。结果:8株细菌含有I类整合子,整合子大小分别为600 bp、1 700 bp和2 500bp,600 bp整合子含基因盒dfr2d,1 700 bp整合子含基因盒dfr17-aadA5。结论:整合子在介导细菌耐药性方面发挥着重要作用。

Objective： To explore the molecular mechanism of class 1 integrons in mediation of antibiotic resistance in isolates of Escherichia coli from blood infection.Methods： The antimicrobial susceptibility test of 16 Escherichia coli isolates were performed by Microscan WalkAway40 and the disk diffusion assay. Class 1 integrons were detected by PCR with total DNA. The purified amplicons of class 1 integrons were sequenced, and gene cassettes were identified.Results： 8 isolates carried class 1 integrons. The sizes of class 1 integrons were 600bp, 1700bp and 2500bp respectively. 600bp integron carried gene cassette dfr2d, and 1700bp integron carried gene cassette dfr17- aadA5 .Conclusion： Integrons play an important role in mediation of antibiotic resistance.