Role of ionic strength in colicin K adsorption.

The rate of colicin K adsorption to Escherichia coli, and consequent death of the bacteria, is progressively inhibited with increasing ionic strength of the medium. Comparison of the kinetics of colicin adsorption with the kinetics of colicin killing suggests that the lethal event provoked by colicin occurs soon after irreversible colicin adsorption. Factors, such as salts, which protect bacteria against the lethal action of colicin act by preventing colicin adsorption.