Effects of anticancer platinum compounds on Escherichia coli strains with normal and defective DNA repair capacity.

The effect of anticancer platinum compounds on isogenetic strains of Escherichia coli with normal or defective DNA repair capacity were studied. Cisdichlorodiammineplatinum (II) causes DNA damage that is repairable by the repair systems of bacteria, and the DNA lesion becomes mutational when processed by the excision repair system. Dinitrato (1R, 2S-cyclohexanediamine) platinum (II) exhibits similar killing activity on E. coli strains with both normal and defective DNA repair capacity. Thus, this compound may cause DNA damage that cannot be repaired by bacteria, or its killing activity may be due to effects other than DNA damage.