Inhibition Effect of Honggumycin on Drug Resistance R Plasmid Transfer Between Bacteria

Abstract

Shigella flexneri D15 R-plasmid CmR and Escherichia coli 1485 RifR were used to investigate the possible inhibition influence of Honggumycin on conjugative drug resistance R plasmid transfer between bacteria and elimination of R plasmid from the objective bacteria.30 μg/mL of Honggumycin was mixed with S.flexneri D15 R-plasmid CmR or E.coli 1485 RifR,which were separately cultured for 24 h and 48 h on MacConkey agar with or without chloromycetin.The inhibition rate and elimination rate of R plasmid were calculated according to the number of colonies from test group and control group.The results indicated that the transfer rate of R plasmid reached 92.82% and 96.04% in the medium with 30 μg/mL of Honggumycin for 24 h and 48 h,respectively.Besides,there was no significant effect of Honggumycin on elimination of R plasmid from S.flexneri D15 R-plasmid CmR.Therefore,Honggumycin could effectively inhibite conjugative R plasmid transfer from S.flexneri D15 R-plasmid CmR to E.coli 1485 RifR and was impossible to eliminate R plasmid.