天津医药

天津医药 ›› 2015, Vol. 43 ›› Issue (4): 404-407.doi: 10.11958/j.issn.0253-9896.2015.04.019

• 专题研究·细菌与耐药 • 上一篇    下一篇

志贺菌属外排泵AcrAB-TolC 及其调控基因突变与氟喹诺酮耐药性的关系

杨贤1，董利娟1，祁伟1△，程玉谦1，吕星2，梁帆3   

  1. 1天津医科大学第二医院感染研究所(邮编300211)；2天津医科大学总医院；3天津市儿童医院
  • 收稿日期:2014-06-18 修回日期:2014-11-20 出版日期:2015-04-15 发布日期:2015-04-13
  • 通讯作者: 祁伟 E-mail:qiweiwyx@yahoo.com
  • 作者简介:杨贤（1987），女，硕士在读，主要从事志贺菌耐药性方面研究

Relationship of AcrAB-TolC efflux pump and its regulatory gene mutation with fluoroquinolones resistance by Shigella.spp

YANG Xian1，DONG Lijuan1，QI Wei1△，CHENG Yuqian1, LYU Xing2, LIANG Fan3   

  1. 1 Second hospital of Tianjin Medical University Institute of Infectious Disease, Tianjin 300211, China; 2 Tianjin Medical University General Hospital; 3 Tianjin Children’s Hospital
  • Received:2014-06-18 Revised:2014-11-20 Published:2015-04-15 Online:2015-04-13
  • Contact: QI Wei E-mail:qiweiwyx@yahoo.com

PDF (PC)

3899

摘要： 摘要：目的探讨临床分离耐氟喹诺酮志贺菌外排泵AcrAB-TolC 基因及其调控基因marOR、acrR、soxS 突变与耐药性的关系。方法使用K-B 纸片扩散法筛选临床耐药菌，测定加入泵抑制剂羰基氢氯苯腙（CCCP）后萘啶酸、左氧氟沙星、氧氟沙星、环丙沙星、诺氟沙星的最低抑菌浓度(MIC)的变化，PCR 扩增外排泵基因acrA、acrB 及其调控基因marOR、acrR、soxS 并测序。结果159 株志贺菌中共筛选出11 株氟喹诺酮耐药菌株；加入质子泵抑制剂后2 株耐药菌株对氟喹诺酮类抗菌药的MIC 下降；7 株耐药菌对氟喹诺酮类抗菌药的MIC 不变；2 株耐药菌对氟喹诺酮类抗菌药的MIC 上升。基因测序发现氟喹诺酮耐药菌株外排泵AcrAB-TolC 调控基因marOR 第36、37、38、39 位存在CATT 碱基缺失。结论泵抑制剂可部分抑制外排泵的活性。marOR 突变可能与志贺菌对氟喹诺酮类抗菌药耐药有关。

关键词: 志贺菌属；喹诺酮类；抗药性, 细菌；外排泵AcrAB-TolC；marOR；羰基氢氯苯腙

Abstract: Abstract: Objective To investigate the role of AcrAB-TolC efflux pump in fluoroquinolones resistance by Shigella. spp and to explore the significance of AcrAB-TolC efflux pump on mutation of acrR, soxS and marOR as well as on drug re⁃ sistence. Methods Drug resistant bacteria were selected by Kirby-Bauer disk diffusion test. After addition of efflux pump inhibitor carbonylcyanide-m-chlorophenylhydrazone (CCCP), change of minimal inhibitory concentration (MIC)s of nilidixic acid, Levofloxacin, ofloxacin, ciprofloxacin and Norfloxacin were examined. The DNA binding region of acrA, acrB, soxS, acrR and marOR gene in these mutants were amplified by PCR and sequenced. Results Among the 159 clinical isolates of Shigella，11 strains are resistant to fluoroquinolone. After the addition of CCCP, MICs of 2 fluoroquinolone resistant strains decreased; the MICs of 7 fluoroquinolone resistant strains did not change; MICs of 2 fluoroquinolone resistant strains in⁃ creased. The corresponding nucleotides C, A, T, T on the 36th to 39th of marOR gene were missing, showing by sequencing, in fluoroquinolone resistent strains which might be regulated by the efflux pump gene AcrAB-TolC. Conclusion Efflux pump inhibitor could restrain the activity of efflux partially. The mutations of marOR might play an important role in fluoroquino⁃ lone resistent by shigella.

Key words: shigella, quinolones, drug resistance, bacterial, AcrAB-TolC efflux pump, marOR, carbonylcyanide-mchlorophenylhydrazone (CCCP)