Dataset Information

Early genetic diagnosis of clarithromycin resistance in Helicobacter pylori.

ABSTRACT:

Background

The drug resistance rate of clinical Helicobacter pylori (H. pylori) isolates has increased. However, the mechanism of drug resistance remains unclear. In this study, drug-resistant H. pylori strains were isolated from different areas and different populations of Chinese for genomic analysis.

Aim

To investigate drug-resistant genes in H. pylori and find the genes for the early diagnosis of clarithromycin resistance.

Methods

Three drug-resistant H. pylori strains were isolated from patients with gastritis in Bama County, China. Minimal inhibitory concentrations of clarithromycin, metronidazole, and levofloxacin were determined and complete genome sequencing was performed with annotation. Hp1181 and hp1184 genes were found in these strains and then detected by reverse transcription polymerase chain reaction. The relationships between hp1181 or hp1184 and clarithromycin resistance were ascertained with gene mutant and drug-resistant strains. The homology of the strains with hp26695 was assessed through complete genome detection and identification. Differences in genome sequences, gene quantity, and gene characteristics were detected amongst the three strains. Prediction and analysis of the function of drug-resistant genes indicated that the RNA expression of hp1181 and hp1184 increased in the three strains, which was the same in the artificially induced clarithromycin-resistant bacteria. After gene knockout, the drug sensitivity of the strains was assessed.

Results

The strains showing a high degree of homology with hp26695, hp1181, and hp1184 genes were found in these strains; the expression of the genes hp1184 and hp1181 was associated with clarithromycin resistance.

Conclusion

Hp1181 and hp1184 mutations may be the earliest and most persistent response to clarithromycin resistance, and they may be the potential target genes for the diagnosis, prevention, and treatment of clarithromycin resistance.

SUBMITTER: Li XH

PROVIDER: S-EPMC8240046 | biostudies-literature | 2021 Jun

REPOSITORIES: biostudies-literature

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Publications

Early genetic diagnosis of clarithromycin resistance in <i>Helicobacter pylori</i>.

Li Xiao-Hua XH Huang Yong-Yi YY Lu Lin-Ming LM Zhao Li-Juan LJ Luo Xian-Ke XK Li Ru-Jia RJ Dai Yuan-Yuan YY Qin Chun C Huang Yan-Qiang YQ Chen Hao H

World journal of gastroenterology 20210601 24

<h4>Background</h4>The drug resistance rate of clinical <i>Helicobacter pylori</i> (<i>H. pylori</i>) isolates has increased. However, the mechanism of drug resistance remains unclear. In this study, drug-resistant <i>H. pylori</i> strains were isolated from different areas and different populations of Chinese for genomic analysis.<h4>Aim</h4>To investigate drug-resistant genes in <i>H. pylori</i> and find the genes for the early diagnosis of clarithromycin resistance.<h4>Methods</h4>Three drug- ...[more]

PMID: 34239272

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