军事医学2016，Vol.40Issue(9)：717-721,5.DOI:10.7644/j.issn.1674-9960.2016.09.006
blaCTX-M-55介导的宋内志贺菌耐药机制研究
Resistance mechanisms of blaCTX-M-55 in a clinical Shigella sonnei strain
摘要
Abstract
Objective To characterize the resistance mechanisms of a clinical Shigella sonnei strain harboring blaCTX-M-55 .Methods A double-disk synergy test was conducted to detect ESBL.Antibiotic resistance genes were determined by PCR followed by amplicon sequencing.Conjugation experiments were performed to verify the transferability of the plasmids carrying ESBL genes.The minimum inhibitory concentration values were tested using VITEK 2.The transposition unit was confirmed by DNA sequencer,and the transcriptional start site was identified using primer extension assay.Results Strain #1083 produced CTX-M-55,which was encoded by plasmid p1083-CTXM that could be transferred into E.coli through conjugation experiments to confer corresponding antibiotic resistance to the transconjugant #1083-EC600.The transposition unit mediating the transfer of blaCTX-M-55 was ISEcp1-blaCTX-M-55 -Δorf477.ISEcp1 offered strong promoter regions for the resistance genes,facilitating their expressions.Besides,the expressions were constant,not induced by antibiotics.Conclusion BlaCTX-M-55 on plasmids is the major resistance genes for strain #1083.Their expressions and spread are mediated by the insertion sequence ISEcp1.关键词
宋内志贺菌/blaCTX-M-55/耐药基因/转座单元/表达与传播Key words
Shigella sonnei/blaCTX-M-55/resistance genes/transposition unit/expressions and spread分类
医药卫生引用本文复制引用
蒋晓圆,宋亚军,刘东,徐丽,方海红,冯娇,殷喆,周冬生,王丽,张德福..blaCTX-M-55介导的宋内志贺菌耐药机制研究[J].军事医学,2016,40(9):717-721,5.基金项目
国家自然科学基金青年资助项目（81501779）；安徽省教育厅自然科学基金资助项目 （）
