Analysis of the Effect of Copper on the Virulence of a Pathogenic Escherichia coli Strain

摘要

To investigate the effect of copper on the pathogenic STEC,Escherichia coli (E.coli)strain 107/86 cultured in the medium complemented with 1.0 mmol/L copper was examined for any potential alteration for virulence.The results showed that Cu-treated strain 107/86 displays suppressed growth profile,an impaired ability to adhere to IPEC-J2 cells.and decreased Stx2e production.Reduction of adherence ability under copper treatment was confirmed by QRT-PCR.Meanwhile,the overall bacterial virulence was also attenuated.The Cu-treated 107/86 strain differed from the untreated strain with 33-fold lower activity of AI-2 in quorum sensing system.Less biofilm formation and decreased diameters of flagella motility halo were also detected.Cu-treated strain exhibited 6-fold higher production of outer membrane protein.The medium with copper has multiple adverse effects on 107/86 resulting in significant attenuation of bacterial virulence.This study provides new insights to the antimicrobial effect of copper.