Mitomycin C binding to poly[d(G-m5C)].
Poly[d(G-m5C)] was modified by reductively activated mitomycin C, an anti-tumour drug, under buffer conditions which are known to favour either the B or the Z conformations of DNA. C.d. and 31P-n.m.r. were used to characterize the poly[d(G-m5C)]-mitomycin cross-linked complexes, as well as the effects on the equilibrium between the B and Z forms of the polynucleotide. Mitomycin C appears to inhibit the B-->Z transition, even in the presence of 3 mM MgCl2, while the Z-form of poly[d(G-m5C)] does not interact significantly with the drug under bifunctionally activating conditions; thus no reversion from the Z-form to the B-form of the polynucleotide can be observed under the salt conditions which are required for the Z-form to exist.
Portugal
J
J
Departamento de Biología Molecular y Celular, Centro de Investigación y Desarrollo, CSIC, Barcelona, Spain.
Sánchez-Baeza
F J
FJ
D002942:Circular Dichroism; D003432:Cross-Linking Reagents; D004247:DNA / Q000737:chemistry / Q000187:drug effects / Q000378:metabolism; D009682:Magnetic Resonance Spectroscopy; D016685:Mitomycin / Q000737:chemistry / Q000378:metabolism* / Q000494:pharmacology; D009690:Nucleic Acid Conformation; D011089:Polydeoxyribonucleotides / Q000737:chemistry / Q000378:metabolism*; D013010:Sonication
D003432:Cross-Linking Reagents; D011089:Polydeoxyribonucleotides; D016685:Mitomycin; C029988:poly(dG-m(5)dC).poly(dG-m(5)dC); D004247:DNA