Mechanism Of Spectinomycin Resistance In Neisseria Gonorrhoeae

Objective To evaluate the relationship between spectinomycin resistance in Neissena gonorrhoeae and mutations in the 16 Sr RNA or the rps E gene.Methods Minimum inhibitory concentrations(MICs) of spectinomycin were determined by an agar plate dilution method.Genomic DNA was extracted from 4 clinical isolates of Neisseria gonorrhoeae with different levels of spectinomycin resistance.Then.PCR was performed to amplify the entire rps E gene and the spectinomycin resistance—determining region(SRDR) in the 16 S r RNA gene followed by direct sequencing.Two spectinomyein—sensitive Neissetia gonorrhoeae strains were transformed with the genomic DNA containing the mutant rps E gene.Subsequently,the susceptibility of the transformants to spectinomycin was determined.and PCR was performed to amplify the rps E and 16 S r RNA genes in the transformants followed by sequencing.Results The numbers of strains simultaneously sensitive, resistant to spectinomycin MIC were 2 and 4, respectively. All the 4 spectinomycin—resistant Neisseria gonorrhoeae strains harbored an A70 C transversion in the rps E gene. but no abnormality in the SRDR of the 16 S r RNA gene.No mutations were detected in the spectinomycin—sensitive Neissena gonorrhoeae strains.The A70 C transversion in the rps E gene was also detected in the two Neisseria gonorrhoeae transformants with spectinomycin resistance.Conclusion N. gonorrhoeae has now shown its ability to develop resistance to spectinomycin also and, although the resistance to spectinomycin is exceedingly rare worldwide, Nevertheless, spectinomycin is also an effective alternative for treatment of urogenital gonorrhoea and spectinomycin should be available worldwide, in particular for emergent cases of multidrug resistance, including clinical resistance to extended-spectrum cephalosporins.In conclusion, this study describes the exchange of Thr at position 24 for Pro have an impact on the interaction of the S5 protein with helix 34 of the 16 S r RNA and contribute to spectinomycin resistance. The A70 C point mutation within the rps E gene is associated with spectinomycin resistance in Neissena gonorrhoeae.However, this group of resistant researchers is fewer, limited scope of the study, further research is needed on the mechanism of drug resistance of Neisseria gonorrhoeae...