The role of rdxA gene in Helicobacter pylori resistant to metronidazole
- VernacularTitle:rdxA基因在幽门螺杆菌对甲硝唑耐药机制中的作用
- Author:
Hui LIN
;
Xiaowei PENG
;
Liping HE
- Publication Type:Journal Article
- Keywords:
Helicobacter pylori;
Metronidazole;
Gene
- From:
Chinese Journal of Digestion
1998;0(06):-
- CountryChina
- Language:Chinese
-
Abstract:
8 mg/L). The rdxA gene fragment (886 bp) of H. pylori was amplified by PCR and then sequenced. Finally polymorphism analysis was performed in the rdxA gene sequence from those strains resistant or susceptible to Mtz and standard strains H.pylori 26695. Results A total of 47 H.pylori strains were isolated from 51 patients positive for rapid urease test. Mtz resistance rate was 34% by E-test method and 31.9% by breakpoint susceptibility testing. Among them 15 strains were resistant to Mtz by the two tests. The rdxA genes of both 15 strains resistant to Mtz and 8 strains susceptible to Mtz were sequenced. Compared with that of strain H.pylori 26695, the sequence of rdxA gene nucleotide in 15 H.pyloristrains resistant to Mtz showed similarity ranging from 90% to 95% and being 92.5% on average, and the sequence of rdxA gene nucleotide in susceptible strains showed similarity ranging from 94% to 95% and being 94.5% on average. In most resistant strains, the rdxA genes occurred point mutation, single nucleotide insertion or deletion, however, the insertion or deletion of large nucleotide fragment were rare, and mutational site were variable. Conclusions The rdxA gene mutation in H.pylori strains resistant to Mtz may result from point mutations in several bases or insertional mutations or deletional mutations in one base, without insertion or deletion of large neuclectide fragment, and mutational position being variable.
