Structure of RdxA - an oxygen-insensitive nitroreductase essential for metronidazole activation inHelicobacter pylori
نویسندگان
چکیده
منابع مشابه
Role of NADPH-insensitive nitroreductase gene to metronidazole resistance of Helicobacter pylori strains
BACKGROUND AND THE PURPOSE OF THE STUDY Current anti-H. pylori therapies are based on the use of two antibiotics with a proton pump inhibitor and/or a bismuth component. Metronidazole is a key component of such combination therapies in Iran. The aim of this study was to determine the role of rdxA gene in resistant strains of H. pylori isolated from Shahrekord Hajar hospital to metronidazole. ...
متن کاملMutations in Helicobacter pylori rdxA gene sequences may not contribute to metronidazole resistance.
Metronidazole resistance in Helicobacter pylori reportedly occurs by mutational inactivation of the oxygen-insensitive nitroreductase gene rdxA. Nucleotide sequences of rdxA were determined in a set of 46 isolates from 19 dyspeptic patients from the UK. The study set comprised matched isolates that were either metronidazole susceptible (four) or mixed metronidazole susceptible and metronidazole...
متن کاملSequential inactivation of rdxA (HP0954) and frxA (HP0642) nitroreductase genes causes moderate and high-level metronidazole resistance in Helicobacter pylori.
Helicobacter pylori is a human-pathogenic bacterial species that is subdivided geographically, with different genotypes predominating in different parts of the world. Here we test and extend an earlier conclusion that metronidazole (Mtz) resistance is due to mutation in rdxA (HP0954), which encodes a nitroreductase that converts Mtz from prodrug to bactericidal agent. We found that (i) rdxA gen...
متن کاملRole of the rdxA and frxA genes in oxygen-dependent metronidazole resistance of Helicobacter pylori.
Almost 50 % of all Helicobacter pylori isolates are resistant to metronidazole, which reduces the efficacy of metronidazole-containing regimens, but does not make them completely ineffective. This discrepancy between in vitro metronidazole resistance and treatment outcome may partially be explained by changes in oxygen pressure in the gastric environment, as metronidazole-resistant (MtzR) H. py...
متن کاملMetronidazole activation is mutagenic and causes DNA fragmentation in Helicobacter pylori and in Escherichia coli containing a cloned H. pylori RdxA(+) (Nitroreductase) gene.
Much of the normal high sensitivity of wild-type Helicobacter pylori to metronidazole (Mtz) depends on rdxA (HP0954), a gene encoding a novel nitroreductase that catalyzes the conversion of Mtz from a harmless prodrug to a bactericidal agent. Here we report that levels of Mtz that partially inhibit growth stimulate forward mutation to rifampin resistance in rdxA(+) (Mtz(s)) and also in rdxA (Mt...
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ژورنال
عنوان ژورنال: FEBS Journal
سال: 2012
ISSN: 1742-464X
DOI: 10.1111/febs.12020