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DNA sequence analysis of rdxA and frxA from 12 pairs of metronidazole-sensitive and -resistant clinical Helicobacter pylori isolates.
| Content Provider | Semantic Scholar |
|---|---|
| Author | Kwon, Dong Hyeon Hultén, Kristina G. Kato, Mototsugu Kim, Jae Jun. Lee, M. M. El-Zaatari, Fouad A. K. Osato, Michael S. Graham, David Y. |
| Copyright Year | 2001 |
| Abstract | We previously reported that inactivation of rdxA and/or frxA converted Helicobacter pylori from metronidazole sensitive to metronidazole resistant. To examine the individual roles of rdxA and frxA in the development of metronidazole resistance in H. pylori, we examined the status of rdxA and frxA from 12 pairs of metronidazole-sensitive and -resistant H. pylori isolates obtained following unsuccessful therapy containing metronidazole. Arbitrary primed fingerprinting analyses revealed that the genotypes of 11 sensitive and resistant pairs of strains were essentially identical. Amino acid sequence identities of RdxA and FrxA from the 14 metronidazole-sensitive isolates ranged from 92 to 98% and 95 to 98%, respectively, compared to that of H. pylori J99 (MIC, 1 microg/ml). All strains with high-level metronidazole resistance (MICs, 128 microg/ml) contained premature truncation of both RdxA and FrxA caused by nonsense and/or frameshift mutations. Strains with intermediate resistance to metronidazole (MICs, 32 to 64 microg/ml) contained a single premature truncation and/or altered RdxA and FrxA caused by nonsense, frameshift, and unique missense mutations. The low-level metronidazole-resistant strains (MICs, 8 microg/ml) contained unique missense mutations in FrxA but no specific changes in RdxA. The results demonstrate that alterations in both the rdxA and frxA genes are required for moderate and high-level metronidazole resistance and that metronidazole resistance that develops during anti-H. pylori therapy containing metronidazole is most likely to involve a single sensitive strain infection rather than a coinfection with a metronidazole-resistant strain. |
| Starting Page | 16 |
| Ending Page | 19 |
| Page Count | 4 |
| File Format | PDF HTM / HTML |
| Alternate Webpage(s) | http://aac.asm.org/content/45/9/2609.full.pdf |
| PubMed reference number | 11502537v1 |
| Volume Number | 45 |
| Issue Number | 9 |
| Journal | Antimicrobial agents and chemotherapy |
| Language | English |
| Access Restriction | Open |
| Subject Keyword | Amino Acids Coinfection Contain (action) Frameshift Mutation function Genotype Helicobacter pylori Ab:ACnc:Pt:Ser:Qn Metronidazole Missense Mutation Nonsense mutation Protein Truncation Abnormality Sense of identity (observable entity) Sequence Analysis |
| Content Type | Text |
| Resource Type | Article |
