Definitions of Dactinomycin

  1. An antitumor antibiotic derived from Streptomyces parvullus. It binds to DNA and inhibits RNA synthesis ( transcription), with chain elongation more sensitive than initiation, termination, or release. As a result of impaired mRNA production, protein synthesis also declines after dactinomycin therapy. ( From AMA Drug Evaluations Annual, 1993, p2015)