替加环素耐药机制研究进展

Advance on the Tigecycline Resistance Mechanism

替加环素作为新型四环素类抗生素,是治疗产碳青霉烯酶多重耐药肠杆菌感染的最后一道防线之一。近年来,替加环素耐药菌株的出现严重限制了替加环素的临床使用。最初认为替加环素的耐药机制是由染色体编码的外排泵介导,不能通过水平转移导致菌株耐药。随着研究的深入,发现质粒上的某些外排泵突变或高表达也可导致菌株替加环素敏感性降低。最近报道质粒介导的tet(X)变异体能够使菌株对替加环素产生高水平耐药,并通过可接合性质粒在不同种属细菌间传播。文章通过介绍细菌染色体介导替加环素耐药机制以及质粒介导的替加环素耐药机制,阐述了高水平替加环素耐药基因tet(X)变异体的流行情况和传播机制,并对动物源菌株出现高水平替加环素耐药基因tet(X)变异体提出合理性解释,旨在为相关科研人员和临床工作者提供参考。

Tigecycline,as a new tetracycline antibiotic,is one of the last lines of defense against carbapenems-producing enterobacter multidrug-resistant infections.In recent years,the emergence of tigecycline-resistant strains has severely restricted the clinical use of tigecycline.It was originally believed that the resistance mechanism of tigecycline was mediated by the efflux pump encoded by the chromosome,which could not lead to drug resistance by horizontal transfer.With the deepening of research,it was found that some efflux pump mutations or high expression on the plasmid could also cause the strain’s tigecycline sensitivity to decrease.Recently,it has been reported that the plasmid-mediated tet(X)variant can make the strain highly resistant to tigecycline,and can be spread among different species of bacteria through adaptable plasmids.This article described the prevalence and transmission mechanism of high-level tigecycline resistance gene tet(X)variants by introducing bacterial chromosome-mediated tigecycline resistance mechanisms and plasmid-mediated tigecycline resistance mechanisms,and provided a reasonable explanation for the high-level variant of the tigecycline resistance gene tet(X)in animal-derived strains,aiming to provide reference for relevant scientific researchers and clinical workers.