Analysis of Drug Resistance in Helicobacter Pylori by Complete Genome Sequencing in Bama County, Guangxi, China

Background: The resistance rate of clinical Helicobacter pylori (Hp) isolates has increased, however, the mechanism of drug resistance is unclear. In this study, we isolated drug-resistant Hp strains isolated from different areas and different populations of China for genomic analysis.Objectives: The aim of this study was to investigate drug resistance in Hp from Bama County, Guangxi, China.Methods: Minimal inhibitory concentrations (MICs) of clarithromycin, metronidazole and levofloxacin were determined and complete genome sequencing was performed with annotation. The presence of hp1181 and hp1184 genes was detected by RT-PCR. The relationships between hp1181, hp1184 and clarithromycin resistance were confirmed by gene mutation and drug-resistant strains. Results: Three drug-resistant Hp strains were isolated from patients with gastritis in Bama County. The strains showed a high degree of homology with hp26695 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 on drug-resistant genes indicated that the RNA expression of hp1181 and hp1184 increased in the three strains that were the same in the artificially induced clarithromycin-resistant bacteria. After gene knockout, the drug sensitivity of the strains increased significantly.Conclusions: The expressions of the genes hp1184 and hp1181 were associated with clarithromycin resistance in the Hp from Bama, Guangxi.