DNA Cleavage, Peroxide Adduct of Binuclear Iron(III), Interaction with Sugar moietyWe have in this study obtained the experimental evidence to suggest that the peroxide adduct of binuclear iron(III) complex with H(HPTP) directly reacts with the sugar moiety of the DNA chain, to cleave it; H(HPTP) denotes N,N.N',N'-tetrakis(2-pyridylmethyl)-l,3-diamino-2 -propanol.In tro d u c tio n
Bleom ycins(BLM ) are a group o f antitumor an tibiotics, first isolated by Umezawa in 1966 [1]. These compounds are used clinically in the treat ment for head and neck cancer, testicular cancer, and squamous carcinomas [2]; their cytotocity is thought to be related to their ability to bind and tdegrade double-stranded DNA [3]. Extensive ef forts by numerous investigators in the past decade have provided much information about the prod ucts during BLM-mediated degradation o f DNA and the chemistry o f their formations [4, 5].In cubation o f BLM with Fe2+ and O2 yields a mixture o f ferric-BLM and "activated BLM", a species re cently shown to contain BLM-ferric-peroxide by electrospray mass spectroscopy [6], However, the discussion how the metal-peroxide adduct cleaves D NA is scarce [7], and also there's no evidence to support that the peroxide adduct reacts directly with DNA [8]. In this study we will show clear evidence that the peroxide adduct o f a binuclear iron(III) re acts directly with DNA to degrade it.