Characteristics Of Conjugation And Transfer Of Drug-resistant Plasmids By Acid Preparations Commonly Used In Veterinary Clinic Impact Study

In recent years,the irrational use of antimicrobial drugs worldwide has led to the development of serious resistance to commonly used drugs in the main pathogenic bacteria in veterinary practice.The emergence and prevalence of antibiotic resistance poses a serious risk to human and animal health,and plasmid-mediated horizontal gene transfer(HGT)plays an important role in this process.The relationship between non-antibiotic drugs and the spread of antibiotic resistance genes(ARGs)in the environment has received considerable attention in the face of increasing antibiotic pressure and the spread of antimicrobial resistance genes.To this end,this study investigates the impact of acid formulations commonly used in veterinary practice on the splice transfer of plasmid-borne ARGs.The study consists of three parts as follows:First,strains containing the tet(X4)plasmid,tet M plasmid,tet L plasmid,mcr-1 plasmid and two model bacteria made by electroshock transformation were used to construct splice systems.The frequency of splicing was increased by 2 to 7 times at 0.1%formic acid,1%lactic acid,1%phosphoric acid and 1%citric acid concentrations,37°C was the optimum splicing temperature and the optimum splicing time was when the splicing time exceeded 12 h.Secondly,to further investigate the effect of acid preparations on splice transfer,phenotypic tests were carried out using donor bacteria Z14 and recipient bacteria A10.When four acid preparations(formic acid,lactic acid,phosphoric acid and citric acid)were added respiration levels were significantly inhibited,SOD activity was inhibited,reactive oxygen species were enhanced and cell membrane permeability increased in Z14 and A10 donor and recipient bacteria.ATP production decreased and NAD~+/NADH decreased.Finally,the effect of acid formulation on the in vivo drug-resistant flora and resistance gene abundance was investigated by feeding mice with acid formulation in drinking water,constructing an in vivo model and analysing the intestinal contents flora using a macro-genomic approach.The results showed that the addition of acid preparations led to an increase in intestinal flora richness and increased diversity of resistance genes.The involvement of pathways such as cellular processes,environmental information processing,genetic information processing,human disease,metabolism,organismal systems,and drug development was increased.In conclusion,this study determined the effect of acid agents on the splice transfer of drug-resistant plasmids and these findings provide new insights into the spread of ARGs.