gyrA、parC及mdfA基因测序鉴定肺炎克雷伯菌

Identification of clinical isolates of Klebsiella pneumoniae by sequencing of genes gyrA,parCand mdfA

目的探讨gyrA、parC和mdfA基因测序鉴定临床分离的泛耐药肺炎克雷伯菌的必要性。方法采用gyrA、parC和mdfA基因测序方法对经法国生物梅里埃公司API 20E系统(API LAB plus)和MicroScan WalkAway96Plus全自动细菌鉴定系统鉴定为克雷伯菌属或产气肠杆菌的19株临床分离株进行分子鉴定。结果 19株菌gyrA、parC、mdfA基因PCR扩增均阳性,基因序列经GenBank中的BLASTn程序进行同源性比较分析,表明与2株完成全基因组测序的肺炎克雷伯菌肺炎亚种NTUH-K2044(Accession:AP006725.1)和MGH 78578(Accession:CP000647.1)最为接近,均为99.0%同源,证实19株均为肺炎克雷伯菌。结论采用gyrA、parC和mdfA基因测序鉴定肺炎克雷伯菌结果准确。

OBJECTIVE To explore the effectiveness of identifying clinically isolated pan-resistant Klebsiella pneu- moniae by sequencing of genes gyrA, parC and mdfA. METHODS Totally 19 strains of bacteria were identified as pan-resistant Klebsiella or E. aerogenes by bacteria classification systems （BioMerieux API 20 E and MicroSean WalkAway 96 Plus）. The genome of the same group of strains were amplified by PCR and sequenced for genes gyrA, parC and mdfA. RESULTS Of the 19 strains tested, the positive rate of genes gyrA, parC and mdfA were all 100.0%. The homology analysis indicated that the amplified genes of gyrA, parC and mdfA had 99.0% homology with 2 strains of complete genome sequence K. pneumoniae subsp, pneumoniae NTUH-K2044（Accession：AP006725.1） and K. pneumoniae subsp, pneumoniae MGH 78578 （Accession： CP000647. 1） ; all the 19 strains were confirmed as K. pneumoniae. CONCLUSION It is proved that the method of identifying K. pneumoniae via gene sequencing of gyrA, parC and rndfA is accurate.