淋球菌mtr系统的IR区基因突变与其多重耐药性的关系

The Mutation of IR Gene in the mtr System and Multiple Antibiotic Resistance of Neisseria gonorrhoeae

目的探索多传递耐药(mtr)系统反向重复序列(IR)区基因突变与淋球菌染色体介导多重耐药性的关系。方法琼脂稀释法做淋球菌药敏试验,选择耐不同药物的菌株,聚合酶链反应扩增包含 IR区的目的基因,然后对扩增产物测序。结果 2株敏感株及5株仅耐青霉素菌株无IR区基因突变,17 株多重耐药菌株中,1株同时耐青霉素和阿奇霉素的淋球菌有IR区碱基T／A,T／A插入,其余耐药株IR区均有碱基A／T缺失。结论淋球菌染色体mtrR启动子区域的IR区基因突变会引起淋球菌多重耐药株的产生,增加淋球菌对抗生素的抗性。

Objective To study the relationship between the mutation of the reverted repeat （IR） gene in the multiple transferable resistant （mtr） system and multiple antibiotic resistance of Neisseria gonorrhoeae. Methods The antimicrobial susceptibilities of isolated strains were tested. An agar plate dilution method was used to determine the minimum inhibitory concentrations. The target genes were amplified by PCR and subjected to sequencing. Results No mutation was found in the IR gene of either of 2 sensitive or 5 penicillin-resistant Neisseria gonorrhoeae strains. Among the 17 multiple-antibiotic-resistant strains, a strain with both azithromyein- and penicillin-resistance had T/A and T/A insertions, and another had A/T deletion. Conclusion Mutations in the IR gene of the mtr system of Neisseria gonorrhoeae might result in multiple antibiotic resistance.