携带bla_(KPC-2)基因泛耐药肺炎克雷伯菌可移动遗传元件分析  

Investigation of mobile genetic elements in pandrug-resistant Klebsiella pneumoniae harboring bla_(KPC-2) type carbapenemase gene

作　　者：黄支密[1] 夏守慧[1] 周芸[1] 杨伟平[1] 李洁[1] 糜祖煌[2] 

机构地区：[1]中国人民解放军第九八医院检验科,湖州313000 [2]无锡新区虎马生物信息工作室/无锡市克隆遗传技术研究所,无锡214026

出　　处：《中国抗生素杂志》2017年第2期139-143,共5页Chinese Journal of Antibiotics

摘　　要：目的了解临床分离的携带bla_(KPC-2)型碳青霉烯酶基因泛耐药肺炎克雷伯菌中可移动遗传元件(mobile genetic elements,MGEs)存在情况。方法在2008年11月至2009年7月从住院患者中分离19株携带blaKPC-2型碳青霉烯酶基因泛耐药肺炎克雷伯菌,通过分析3种基因gyrA、parC和mdfA序列对菌株进行分子鉴定。采用PCR方法检测4种可移动遗传元件遗传标记基因,分别为:泛宿主性接合性质粒遗传标记trbC、转座子Tn1548遗传标记tnpU、Ⅰ类整合子遗传标记qacE△1‐sul1和插入序列共同区遗传标记ISCR1基因;对扩增阳性的4种遗传标记基因PCR产物采用双向测序,测序结果用Chromas软件直接作BLAST Search比对分析。结果本组19株gyrA、parC和mdf A基因PCR扩增均阳性,其基因序列经Gen Bank中的BLASTn程序进行同源性比较分析,证实19株均为肺炎克雷伯菌。19株中,4种可移动遗传元件遗传标记trbC、tnpU、qacE△1‐sul1和ISCR1基因阳性率均为100.0%,经对该4种遗传标记基因PCR阳性产物进行测序比对,发现与Gen Bank中已发布的4种相对应基因trbC、tnpU、qacE△1‐sul1和ISCR1序列完全相同(同源性均为100.0%),均得到确认。结论可移动遗传元件在携带bla_(KPC-2)型碳青霉烯酶基因泛耐药肺炎克雷伯菌中广泛存在。Objective To investigate the distribution of mobile genetic elements （MGEs） in pandrug-resistant Klebsiella pneumoniae harboring blanc.2 type carbapenemase gene, isolated from the 98th Hospital of People,s Liberation Army, Huzhou District, Zhejiang province. Methods Nineteen strains of pandrug-resistant Klebsiella pneumoniae harboring blanc.2 type carbapenemase gene were isolated from the inpatients between November, 2008 and July, 2009. Molecular identification ofKlebsiella pneumoniae clinical isolates were carried out by the sequencing of genes gyrA, parC and mdfA. Four kinds of mobile genetic elements marker of genes trbC, tnpU, qacE△l-sull and 1SCR1 were amplified by PCR and were verified by DNA sequencing. The genes tested were pan host conjugate plasmid genetic marker trbC, transposons Tn1548 genetic marker tnpU, class 1 integrons genetic marker qacE△1- sull, and insertion sequence common region genetic marker 1SCR1, respectively. The genetic marker gene sequence were analyzed by Chromas and GenBank BLASTn algorithm for its homology. Results For the 19 strains tested, the positive rate of genes gyrA, parC and mdfA were all 100.0%. Homology analysis by GenBank BLASTn indicated that the amplified genes ofgyrA, parC and mdfA had 99.0% homology with two strains of complete genome sequence Klebsiella pneumoniae subsp, pneumoniae （Accession：AP006725.1 and CP000647.1）, and all the 19 strains were confirmed as Klebsiella pneumoniae. For the 19 strains tested, the positive rate of mobile genetic elements marker of genes oftrbC, tnpU, qacEAl-sull andlSCR1 were all 100.0%. Homology analysis by GenBank BLASTn indicated that the amplified genes of trbC, tnpU, qacEAl-suH and 1SCR1 had 100.0% homology with four kinds of corresponding gene sequence registered in GenBank, and all were confirmed. Conclusion Mobile genetic elements are prevalent in pandrug-resistant Klebsiellapneumoniae harboring blaKPC-2 type carbapenemase gene isolated from the inpatients.

关 键 词：肺炎克雷伯菌 blaKPC-2 碳青霉烯酶 可移动遗传元件 插入序列共同区 基因 分子鉴定 

分 类 号：R937[医药卫生—生药学]