Genetic Diversity of CMY Beta-Lactamase Genes in Clinical Isolates of Escherichia coli in Myanmar: Identification of Three Novel Types and Updated Phylogenetic Classification of bla(CMY)
Genetic Diversity of CMY Beta-Lactamase Genes in Clinical Isolates of Escherichia coli in Myanmar: Identification of Three Novel Types and Updated Phylogenetic Classification of bla(CMY)
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缅甸大肠杆菌临床分离株中 CMY β-内酰胺酶基因的遗传多样性：三种新类型的鉴定和 bla(CMY) 的更新系统发育分类
DOI：
10.1089/mdr.2019.0234
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发表时间：
2019
影响因子：
2.6
通讯作者：
Kobayashi N
中科院分区：
文献类型：
--
作者：
San N;Aung MS;Urushibara N;San T;Maw WW;Lwin MM;Mar TT;Myint YY;Thu PP;Hlaing MS;Ganesh B;Kobayashi N
cmy型酶是质粒介导的AmpC β -内酰胺酶之一，在肠杆菌科的传播已成为一个重要的公共卫生问题。本研究对缅甸仰光426株大肠杆菌临床分离株中50株blacmy阳性分离株的CMY β -内酰胺酶基因的遗传多样性进行了研究。CMY基因共分为9个类型，以blacmy -42型居多（22株，占44%），其次为blacmy -2、blaCMY-6、blaCMY-146，并包括3个新类型（CMY-156、CMY-158、CMY-159）。AmongE。系统发育组d序列型（ST）405和A-ST410是最常见的基因型，72%（36/50）的分离株检测到blactx - m -15。blacmy -42分布在A、B1和DE. colioli的系统发育类群中，共有11个STs，其中10个分离株含有碳青霉烯酶基因（blaNDM-4、blaNDM-5、orblaNDM-7）。对迄今报道的所有blacmy基因（包括本研究中的3个新类型）的系统发育分析显示，存在至少4个不同的遗传组，即CMY-1、CMY-2、CMY-70和CMY-98组，不同组之间的核苷酸序列同源性低于91%。CMY-2组β -内酰胺酶基因包含CMY类型最多（89.7%），具有广泛的多样性，可分为I和II两类。本研究鉴定的8种CMY类型被归为CMY-2组I类，而新型CMY-159型被归为CMY-98组，泰国的CMY-98组含有freundidistrain单胞杆菌。
The dissemination of CMY-type enzymes, one of the plasmid-mediated AmpC beta-lactamases, among Enterobacteriaceae has become an important public health concern. In this study, genetic diversity of CMY beta-lactamase genes was investigated for 50blaCMY-positive isolates detected from 426 clinical isolates ofEscherichia coliin Yangon, Myanmar. CMY genes were differentiated into 9 types, withblaCMY-42being predominant (22 isolates, 44%), followed byblaCMY-2,blaCMY-6,blaCMY-146, and included three novel types (CMY-156, CMY-158, CMY-159). AmongE. coliharboringblaCMY, phylogenetic group D-sequence type (ST)405 and A-ST410 were the most common genotypes, andblaCTX-M-15was detected in 72% (36/50) of isolates.blaCMY-42was distributed to phylogenetic groups A, B1, and DE. coliwith 11 STs, which included 10 isolates harboring carbapenemase genes (blaNDM-4,blaNDM-5, orblaNDM-7). Phylogenetic analysis of all theblaCMYgenes reported to date, including the three novel types in the present study, revealed the presence of at least four distinct genetic groups, that is, CMY-1, CMY-2, CMY-70, and CMY-98 group, showing less than 91% nucleotide sequence identities among different groups. CMY-2 group beta-lactamase genes, which contained by far the largest number of CMY types (89.7%) with extensive diversity, were divided into two clusters (I and II). While eight CMY types identified in the present study were classified into CMY-2 group cluster I, novel type CMY-159 was assigned into CMY-98 group with aCitrobacter freundiistrain in Thailand.