摘要
检测了不同时期从河南省分离的162株bla_(CTX-M)型鸡大肠杆菌对黏菌素的耐药性,进行了耐药基因bla_(CTX-M)和mcr-1的质粒接合试验,并比较了各亚型的水平传播规律。结果表明:随着时间的推移,bla_(CTX-M)型鸡大肠杆菌对黏菌素的耐药率由0%显著增加到42.2%;在头孢噻肟单药筛选下获得的21株接合子有5株同时携带mcr-1,在黏菌素单药筛选下获得的18株接合子有11株同时携带bla_(CTX-M),且bla_(CTX-M)和mcr-1基因的接合频率无明显差异;原菌及对应接合子的bla_(CTX-M)亚型均属于bla_(CTX-M-1)和bla_(CTX-M-9)亚群,部分原菌同时携带两种亚型,但接合子均仅携带一种亚型(bla_(CTX-M-9)亚群)。说明在单一药物(黏菌素或头孢噻肟)的选择性压力下,bla_(CTX-M)和mcr-1基因均易水平传播,且携带bla_(CTX-M)和mcr-1的质粒既可单独转移也可同时转移。
In this study,162 strains of bla_(CTX-M) E.coli resistant to colistin from chicken in Henan Province at different time were detected,and plasmid conjugation test of bla_(CTX-M) and mcr-1 were performed to compare the resistance.Meanwhile,the horizontal transmission of each subtype was compared.The results showed that the resistance rate of E.coli to colistin in bla_(CTX-M)-producing chickens increased significantly from 0 to 42.2% over time.Five of 21 transconjugants harbored mcr-1 gene under selective pressure of cefotaxime,and 11 of 21 transconjugants harbored bla_(CTX-M) under selective pressure of colistin.There was no significant difference in the conjugation frequency between bla_(CTX-M) and mcr-1 gene.The detection results of bla_(CTX-M) protozoan and corresponding conjugates found that all subtypes belong to bla_(CTX-M-1) and bla_(CTX-M-9) subgroups,and some protozoa carry two subtypes,but the conjugates carry only one subtype(bla_(CTX-M-9)).The bla_(CTX-M) and mcr-1 were easier to carry out horizontal transfer.Meanwhile,plasmids carrying bla_(CTX-M) and mcr-1 can be transferred alone or simultaneously under selective pressure of a single drug(colistin or cefotaxime).
作者
李文娅
贾雅婷
李垠树
丁海峰
孙华润
胡功政
苑丽
LI Wen-ya;JIA Ya-ting;LI Yin-shu;DING Hai-feng;SUN Hua-run;HU Gong-zheng;YUAN Li(College of Animal Medicine,Henan Agricultural University,Zhengzhou 450002,China)
出处
《江西农业学报》
CAS
2021年第7期99-103,共5页
Acta Agriculturae Jiangxi
基金
国家自然科学基金项目(31772800)。
