摘要
目的 研究嗜麦芽窄食单胞菌临床株外排泵SmeDEF的表达与耐药的关系及其表达调控。方法 琼脂稀释法检测嗜麦芽窄食单胞菌对抗生素敏感性并检测泵抑制剂的作用 ,提取临床菌的RNA进行smeD的RT PCR扩增。提取DNA进行smeT片段的PCR扩增 ,扩增产物进行序列分析。结果 随机选取的 6株嗜麦芽窄食单胞菌均有扩增产物。SmeT的N端氨基酸序列相当保守 ,smeD smeT间区测序发现耐药且泵抑制阳性株基因序列与敏感株明显不同。推测与耐药有关的突变出现在smeT的 82～ 16 5区间。结论 嗜麦芽窄食单胞菌临床株SmeDEF外排泵的表达强弱与其耐药性有关。smeDEF基因的表达可能与调控基因间区的变化有关。
Objective To study whether the expression of S me DEF efflux pump in Stenotrophomonas maltophilia play role in antibiotic resi stance, and work on the regulation of the pump expression. Methods Examine the resistance profile of the clinical strains to antimicrobi al by agar dilution and their reaction to pump inhibitor. Investigate the RNA le vel of smeD by RT-PCR, and amplicate smeD-smeT fragment by PCR, then sequence it. Results All 45 strains had positive amplication resul ts. The amino acid sequence of the forepart of SmeT was conservative. In antibio tic-resistant strains that had positive reaction to pump inhibitor, the interge nic sequences of smeD-smeT were different from those in sensitive ones. The var iations possibly involved with resistance occurred in -165～-82nt of smeT, and several nucleic acids before the start codon of smeT. Conclusion The expression level of SmeDEF is related with the antibiotic resistanc e of Stenotrophomonas maltophilia. The possible resistance mechanism include s the variations in the intergenic smeD-smeT sequence. [
出处
《中华微生物学和免疫学杂志》
CAS
CSCD
北大核心
2004年第9期743-747,共5页
Chinese Journal of Microbiology and Immunology
基金
天津市重点攻关课题资助 (基金编号 :0 0 3 113 5 11)
