Effects of iron and copper ions on the inducibility of hydrogen peroxide in E. coli.

Inducing capacities of hydrogen peroxide in SOS chromotest were investigated in the absence and in the presence of iron and copper ions. Strain PQ37 of Escherichia coli and two strains with altered protection against oxidative damage (PQ300 and OG400) were employed. The latter two strains were more sensitive to the hydrogen peroxide inducing activity than strain PQ37. At the concentration of 150 nmol/ml and 300 nmol/ml, iron ions induced SOS response. At the concentration range from 30 nmol/ml to 300 nmol/ml iron enhanced the effects produced by H2O2. Results with copper were negative.