Analysis of the contribution of molecular mechanisms into formation of gonoccocal resistance to tetracycline.

We applied complex genetic analysis for evaluation of tetracycline-resistance markers in 129 clinical strains of Neisseria gonorrhoeae from Central, Privolzhskii, and Siberian regions. For detection of mutations in rpsJ gene and MtrRCDE locus we first used minisequence reaction followed by identification of products by MALDI-TOF mass spectrometry. The incidence of detection of resistance markers among the analyzed strains were: tetM--3.1%, mutations in genes rpsJ--82.2%, penB--62.8%, and mtrR--54.3%. The analyzed genetic markers were not detected in 17.5% strains. tetM gene was detected in only 12.5% strains from the Central Region. No differences were revealed in regional distribution of other genotypes. Genotypes tetM(pres), rpsJ(mut), mtrR(mut), and rpsJ(mut), penB(mut), mtrR(mut) reliably predict tetracycline resistance. Microbiological and genetic testing of tetracycline resistance yielded similar results.