Abstract: Objective To study the relationship between the mutation of the inverted 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 gonorrhoeas strains. Among the 17 multiple-antibiotic-resistant strains, a strain with both azithromycin- 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.

Key words: Neisseria gonorrhoeae, Genes, bacterial, Repetitive sequences, nucleic acid, Microbial sensitivity tests