Author(s)

Jiayi Li, Yaqiong Ye, Sen Zeng, Rengui Chen, Qiliang Huang, Gensheng Xiao, Hua Lou

Corresponding Author

Hua Lou

Abstract

In order to compare the biological characteristics of artificially induced Staphylococcus aureus and primary sensitive Staphylococcus strains, and to explore the resistance mechanism of the artificially induced Staphylococcus aureus. Staphylococcus was used as a test strain. According to NCCLS recommended paper diffusion method, the drug sensitivity test was used to compare the original Staphylococcus and 12 species of Staphylococcus aureus artificially induced by the original sensitive Staphylococcus. The sensitivity of antibiotics. Biochemical tests were used to compare the biochemical characteristics of primary and resistant strains. The 16SrRNA gene and the mecA gene (drug resistance gene) of the primary strain and the resistant strain were amplified by PCR, and the 16S rRNA gene and the mecA gene of the primary strain and the resistant strain were compared. Results Primary Staphylococcus was sensitive or even extremely sensitive to 12 antibiotics. Although resistant to Staphylococcus was completely resistant to β-lactam antibiotics in these 12 antibiotics, it was resistant to other non-β-lactam antibiotics (sugars). The sensitivity of peptides, quinolones, tetracyclines, aminoglycosides is increased. Among them, the sensitivity of aminoglycosides represented by neomycin and glycopeptides represented by vancomycin is particularly high. The results of biochemical tests showed that the ability of Staphylococcus aureus to ferment mannitol was weaker than that of primary bacteria, and it could not ferment mannitol within 24 h and mannitol in 48 h. PCR results showed that both the original Staphylococcus and the resistant strains could amplify the same 16SrRNA gene, but they could not amplify the mecA gene, indicating that the 16SrRNA gene did not mutate, and the primary and resistant bacteria did not contain mecA gene. The relationship between this series of changes in drug-resistant strains and drug resistance still needs further study. Conclusion: When a bacterium is resistant to a certain drug, its sensitivity to other drugs will change accordingly.

Keywords

Staphylococcus, Drug-Resistant Bacteria, 16Srrna Gene, Meca Gene, Comparison Of Biological Characteristics, Drug Resistance Mechanism