Cobalt chelate of bleomycin. II. Binding to deoxyribonucleic acid of Ehrlich solid tumor in mice.

Abstract

Cobalt chelate of bleomycin (Co-BLM) bound deoxyribonucleic acid (DNA) was purified from Ehrlich solid tumor of mice administered with Co-BLM by the extraction from the purified nuclei. In both 57Co-BLM and Co-BLM (14C), the DNA was taken in 99% purity, and the decrease in the specific radioactivity of the Co-BLM=DNA complex was minimized in the course of the purification procedure. The complex was stable in the Sephadex G-100, hydroxyapatite columns and neutral sucrose gradient solution. Moreover, this was stable in the electrophoretic conditions. However, Co-BLM dissociated from DNA by acid, alkaline or heat treatment.