The emergence of blaCTX-M-15-carrying Escherichia coli of ST131 and new sequence types in Western China

Annals of Clinical Microbiology and Antimicrobials

Short Report

Xiaoju Lü¹  Zhiyong Zong¹  Lei Zhang¹ 

[1] Center of Infectious Diseases, West China Hospital, Sichuan University, Guoxuexiang 37, 610041, Chengdu, China;Division of Infectious Diseases, the State Key Laboratory of Biotherapy, Chengdu, China;

关键词: Escherichia coli;    Plasmids;    MLST;    Beta-lactamases;    Antimicrobial resistance;   

DOI  :  10.1186/1476-0711-12-35

 received in 2013-08-21, accepted in 2013-11-24,  发布年份 2013

来源: Springer

【 摘 要 】

BackgroundblaCTX-M-15, the most widely distributed gene encoding extended-spectrum β-lactamases globally, was not common in China. This study was performed to characterize blaCTX-M-15-carrying Escherichia coli in western China.FindingsOut of 144 Escherichia coli isolates from 20 hospitals in western China, 8 were found carrying blaCTX-M-15. blaCTX-M-15 was carried by isolates of ST131and 5 new STs (ST3342, ST3513, ST3516, ST3517 and ST3518). The 5 new STs shared 5 identical alleles out of 7 but only had up to 2 alleles identical to ST131. blaCTX-M-15 was located on plasmids of IncI1 (ST16) or IncFII-related group (four replicon types). The co-transfer of a few antimicrobial resistance genes including qnrA, qnrB, qnrS, qepA, aac (6′)-Ib-cr, aac (3)-II, tetA, blaTEM and blaOXA-1 with blaCTX-M-15 were examined but only blaTEM-1 was found co-transferring with blaCTX-M-15.ConclusionsFive new STs of E. coli and three new types of IncFII-related plasmids carrying blaCTX-M-15 were identified. This study together with several reports suggested that blaCTX-M-15 has emerged in China and the interruption of both vertical and horizontal transmission of blaCTX-M-15 is required to hurdle its further spread.

【 授权许可】

Unknown   
© Zhang et al.; licensee BioMed Central Ltd. 2013. This article is published under license to BioMed Central Ltd. This is an open access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.