Bleomycin is a glycopeptide antitumor antibiotic produced by the bacterium S. verticillus. Its mechanism of action causes single- and double-strand DNA breaks in tumor cells, which interrupts the cell cycle. Bleomycin is thought to achieve this by chelating metal ions, producing a pseudoenzyme that reacts with...

A glycopeptide antibiotic consisting of a mixture of bleomycin sulfate salts. Bleomycin A2 is pictured.

Bleomycin is a complex of 11 glycopeptide antitumor antibiotics originally isolated from Streptomyces verticillus in 1972. The dominant components of the complex are bleomycin A2 and B2 and typically represent >90% of the total weight with the remainder comprising the minor analogues. Bleomycins have found clinical...