title: [Interaction of the antitumor antibiotic olivomycin with Mg2+ ions].
abstract: The study on the mechanisms of olivomycin and olivin interaction with the magnesium ions showed that formation of the olivomycin complexes with Mg2+ involved 2 stages. At the first (rapid) stage Mg2+ is attached to keto-oxygen of the aglycone polycyclic part. At the second (slow) stage the complex is relaxed into the stable state with a more compact configuration. the equilibrium constants (Ce) of the main processes of olivomycin and olivin interaction with Mg2+ were determined. In the first case Ce = 3 . 10(3) M+1 and in the second case Ce = 1.6 . 10(2) M-1. It was shown that the geometric and optic characteristics of the complexes were consistently related: formation of the stable complex was accompanied by a 10-time decrease in the fluorescence quantum efficiency.
mesh_terms: D000873:Anthracenes / Q000032:analysis / Q000494:pharmacology; D002413:Cations, Divalent / Q000494:pharmacology; D004347:Drug Interactions; D007700:Kinetics; D008274:Magnesium / Q000494:pharmacology*; D009848:Olivomycins / Q000032:analysis / Q000494:pharmacology*; D013050:Spectrometry, Fluorescence; D013054:Spectrophotometry, Atomic
chemical_list: D000873:Anthracenes; D002413:Cations, Divalent; D009848:Olivomycins; C033392:olivin; D008274:Magnesium
vernacular_title: Vzaimodeĭstvie protivoopukholevogo antibiotika olivomitsina s ionami Mg2+.