多耐药肺炎克雷伯菌获得性耐药基因及ompK36突变研究

Investigation of Acquired Resistance Genes and Mutation of ompK36 gene in Multi-drug resistant Klebsiella pneumoniae

目的了解1株多耐药肺炎克雷伯菌(MDRKP)获得性耐药基因和膜孔蛋白基因ompK36存在及突变状况。方法将1株对16种抗菌药物均耐药的MDRKP进行了β-内酰胺类、氨基糖苷类获得性耐药相关基因及其载体(整合子、转座子)的遗传标记检测和膜孔蛋白基因ompK36的检测。结果该株MDRKP耐β-内酰胺类药物获得性耐药基因检出TEM-1、SHV-11、KPC-2型(均经测序比对证实),耐氨基糖苷类药物获得性耐药基因检出aac(3)-Ⅱ、ant(3″)-Ⅰ,无16S rRNA甲基化酶基因检出;Ⅰ类整合子遗传标记intⅠ1、qacE△1-sul1阳性、转座子遗传标记merA阳性;检出膜孔蛋白基因ompK36,且存在变异(GGCGAC小片段插入)。结论该株MDRKP耐β-内酰胺类、基糖苷类等抗氨菌药物与该菌携带获得性耐药基因TEM-1、SHV-11、KPC-2型、aac(3)-Ⅱ、ant(3″)-Ⅰ基因相关;另外,该菌膜孔蛋白基因ompK36发生了变异,这可能与β-内酰胺类药物耐药有关联。

OBJECTIVE To investigate the distribution and variety of acquired resistance genes and ompK36 gene for outer membrane porin protein in a strain of multi-drug resistant Klebsiella pneumoniae（MDRKP）.METHODS Thirty kinds of acquired resistance genes to beta-lactam and aminoglycoside antimicrobial agents were detected,including genetic markers of integron and transposon,and ompK36 gene for outer membrane porin protein,in a strain of MDRKP resistant to 16 kinds of antimicrobial agents.RESULTS Acquired resistance genes TEM-1,SHV-11,KPC-2（all confirmed by DNA sequencing and genomic comparison with sequence registered in NCBI） to beta-lactam antimicrobial agents as well as acquired resistance genes aac（3）-Ⅱand ant（3″）-Ⅰto aminoglycoside antimicrobial agents were detected in the strain of MDRKP.However,16S rRNA methylase were not be detected.In addition,genetic markers of class Ⅰ integron,intⅠ1 and qacE△1-sul1,were positive;and genetic marker of transposon,merA,was also positive.Furthermore,ompK36 gene for outer membrane porin protein was detected,and showed mutation（small inserted CGGCGA）.CONCLUSION Carrying acquired resistance genes TEM-1,SHV-11,KPC-2,aac（3）-Ⅱ and ant（3″）-Ⅰon this strain of MDRKP result in drug resistance to beta-lactam and aminoglycoside antimicrobial agents.Moreover,ompK36 gene for outer membrane porin protein shows mutation in this strain of MDRKP,which may correlated with drug resistance to beta-lactam antimicrobial agents.