Early genetic diagnosis of clarithromycin resistance in .

BACKGROUND

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

AIM

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

METHODS

Three drug-resistant 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. and genes were found in these strains and then detected by reverse transcription polymerase chain reaction. The relationships between or and clarithromycin resistance were ascertained with gene mutant and drug-resistant strains. The homology of the strains with 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 and 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 , , and genes were found in these strains; the expression of the genes and was associated with clarithromycin resistance.

CONCLUSION

and 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.