摘要
目的研究多重耐药肺炎克雷伯菌(MDR—KPN)对喹诺酮类药物的耐药机制。方法收集2008年8月至2010年5月浙江省杭州市和湖州市6所医院共47株MDR-KPN,采用聚合酶链反应(PCR)及序列分析方法分析喹诺酮类药物作用靶位编码基因gym、parC和可移动遗传元件介导的喹诺酮类耐药基因[qnrA、qnrB、qnrS、at2C(6’)-Ib—cr、qepA]。结果47株MDR.KPN中检出43株(91.5%)gyrA突变、40株(85.1%)parC突变、3株(6.4%)qnrB2、1株(2.1%)qnrB4、8株(17.0%)qnrSl、5株(10.6%)qnrS4、2株(4.3%)O,6tC(6’).Ib.cr,发现5株gyrA基因新的变异型(GenBank登录号:JN811952、JN811953、JN811954、JN811955、JN811956),5株parC基因新的变异型(GenBank登录号:JN817432、JN817433、JN817434、JN817435、JN817436),qnrS4为首次发现的qnrS变异型(GenBank登录号:JN836269)。结论本组菌株喹诺酮类药物耐药主要与gyrA和parC基因的喹诺酮耐药决定区(QRDR)有义突变相关,部分菌株可检出qnrB2、qnrB4、qnrSl、qnrS4、aac(6’).Ib-cr等可移动遗传元件介导的喹诺酮类耐药基因。检出qnrS4为国内外首次报道。
Objective To investigate the resistant mechanism of quinolones on multi-drug resistant Klebsiella caused pneumonia (MDR-KPN). Methods From August 2008 to May 2010,47 strains of MDR-KPN were collected from 6 hospitals in Hangzhou and Huzhou in Zhejiang province in China. Drug target genes to quinolones (gyrA, parC) and quinolone-resistance genes mediated by mobile genetic elements [qnrA, qnrB, qnrS, aac (6')- I b-cr, qepA] were analyzed by PCR and verified by DNA sequencing. Results Positive results were found in 47 strains of MDR-KPN, 43 strains (91.5%) of gyrA mutation, 40 strains(85.1%) ofparC mutation, 3 strains (6.4%) of qnrB2, 1 strain (2.1%) ofqnrB 4, 8 strains (17.0%) ofqnrS l, 5 strains (10.6%) of qnrS 4,2 strains (4.3%) of aac (6')- I b-cr respectively. Moreover, 5 novel variants ofgyrA (GenBank accession number: JN811952, JN811953, JN811954, JN811955, JN811956) , 5 novel variants of parC (GenBank accession number:YNS17432, JN817433, JN817434, JN817435, YN817436)were also identified. In addition, qnrS4 (GenBank accession number: JN836269) appeared to be the novel variants of qnrS. Conclusion Quinolone-resistance-determining region played a key role on the resistance to quinolones in this group of MDR-KPN, and quinolone-resistance genes mediated by mobile genetic elements [qnrB2, qnrB4, qnrS1, qnrS4, aac (6') - I b-cr] showed positive in some parts of the strains. This was the first report on emergence ofqnrS4 in the world.
出处
《中华流行病学杂志》
CAS
CSCD
北大核心
2013年第1期61-66,共6页
Chinese Journal of Epidemiology
关键词
肺炎克雷伯菌
喹诺酮类
新变异型
喹诺酮耐药决定区
多重耐药
Klebsiella pneumoniae
Quinolone
Novel variant
Quinolone-resistance- determining region
Multi-drug resistance