Cell surface alterations induced by methylene blue and direct electric current in Escherichia coli

Cell surface properties, including hydrophobicity, zeta potential, carbohyd rate and fatty acid components, were altered on treatment off. coli K12 wit h methylene blue (MB) and direct electric current (DC). The treatment of fi mbriated E. coli cells with MB greatly increased the agglutination of yeast cells when compared to untreated bacteria. However, this increased aggluti nation was markedly reduced when the bacteria were treated with MB plus DC. These results suggest that MB modifies cell surface components in the abse nce of light and these alterations are more pronounced when cells are treat ed simultaneously with MB and DC.