The biologically active site of neocarzinostatin-chromophore.
نویسندگان
چکیده
منابع مشابه
Peroxy acid as a partial structure of neocarzinostatin (NCS) chromophore.
Sir: Neocarzinostatin (NCS) chromophore was obtained as a separable component from polypeptide antitumor antibiotic NCS by us1,2) and GOLDBERG et al.3,4), independently. This chromophore, which was demonstrated to have biological activities such as growth inhibition of bacterial and tumor cells1), inhibition of DNA synthesis in cultured mammalian cells, strand scission of DNA in vitro and in vi...
متن کاملRoles of chromophore and apo-protein in neocarzinostatin action.
The methanol-extractable, nonprotein chromophore of the antitumor, protein antibiotic neocarzinostatin (NCS) has at least the full activity of the parent compound in inhibiting DNA synthesis and growth of HeLa cells and in causing DNA strand breaks in vivo and in vitro. In vitro DNA strand scission by the chromophore is markedly stimulated by 2-mercaptoethanol and is inhibited by guanidine hydr...
متن کاملDNA microstructural requirements for neocarzinostatin chromophore-induced direct strand cleavage.
The microstructural requirements for optimal interaction of neocarzinostatin chromophore (NCS-C) with DNA have been investigated using a series of hexadeoxyribonucleotides with modified bases such as O6-methyl G (MeG), I, 5-methyl C (MeC), U, or 5-Bromo U (BrU) at specific sites in its preferred trinucleotide 5'GNaNb3':5'Na,Nb,C3' (Na = A, C, or T). Results show that MeG:C and G:MeC in place of...
متن کاملReversible modification of arginine residues in neocarzinostatin. Isolation of a biologically active 89-residue fragment from the tryptic hydrolysate.
Reaction of the antitumor protein neocarzinostatin with 1,2-cyclohexanedione in 0.25 M borate buffer, pH 9.0, resulted in complete modification of arginine residues in positions 66, 67, and 78. The arginine-modified protein lost its native structure and was biologically inactive in the inhibition of growth of HeLa cells, inhibition of DNA synthesis, and in vitro DNA strand scissions. Trypsin hy...
متن کاملMechanism of free and conjugated neocarzinostatin activity: studies on chromophore and protein uptake using a transferrin-neocarzinostatin conjugate.
Targeting studies using the anti-cancer agent neocarzinostatin (NCS), conjugated to anti-bodies have shown relatively poor specificity. From the literature, it is unclear whether NCS mediates its effects either in conjugated or unconjugated form. In the present work we have used a conjugate of NCS with transferrin, a biological ligand with a well defined endocytic route, to probe these mechanis...
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ژورنال
عنوان ژورنال: Chemical and Pharmaceutical Bulletin
سال: 1986
ISSN: 0009-2363,1347-5223
DOI: 10.1248/cpb.34.4425