金黄色葡萄球菌对苯扎溴铵敏感性与生物被膜形成能力相关性分析OA北大核心CSTPCD

Overall 35 strains of Staphylococcus aureus(S.aureus)isolated from one pig slaugh-terhouse and different pig farms were used as experimental materials to analyze the correlation between the susceptibility of benzalkonium bromide and the biofilm formation ability.Sensitivity to benzalkonium bromide and ability to form biofilms of S.aureus strains were determined using the micro-dilution broth method and the crystal violet staining test,respectively.The multi-locus sequence typing(MLST)and the carrying of genes related to disinfectant resistance and biofilm formation of 26 strains of S.aureus from the slaughterhouse were analyzed based on whole-ge-nome sequences.The results showed that among the 35 strains,the minimum bactericidal con-centration(MBC)of benzalkonium bromide ranged from 1 to 16 mg·L-1,and there were 16 strains with strong biofilm-forming ability,accounting for 45.71％(16/35)of the total,of which 93.75％(15/16)were samples collected from downstream in the slaughter chain.ST7 was the dominant type of S.aureus with strong biofilm-forming ability(93.75％,15/16).The benza-lkonium bromide MBC value of S.aureus was positively correlated with biofilm formation ability(Correlation coefficient=0.690),the disinfectance has nothing to do with the gene.In conclu-sion,biofilm formation may increase S.aureus resistance to disinfectants,weaken the disinfec-tion effect of benzalkonium bromide,thus enhance the risk of bacterial contamination and trans-mission in breeding and slaughtering.