Structure of the intrastrand cis-[Pt(NH3)2(d(GpCpG))] adduct in a dodecanucleotide duplex: I. A 1H and 31P n.m.r. study.
The structure of an intrastrand cis-[Pt(NH3)2(d(GpCpG))] adduct in a dodecanucleotide duplex has been investigated by using ultraviolet absorption, circular dichroism, 1H and 31P n.m.r. The binding of cis-DDP does not inhibit the formation of a duplex but it induces a lowering of congruent to 26 degrees C of its melting temperature. A broadening of the 1H spectrum prevents an accurate analysis of the platination site. Nevertheless, by considering its thermal behavior and the number of imino protons a model of structure of the platinated duplex is proposed in which the central C.G. pair is disrupted and a neighboring C.G pair is very accessible or distorted. The environment of two phosphate groups is disturbed by the cis-DDP binding.
Centre de Biophysique Moléculaire (CNRS), Université d'Orléans, France.
M
M
Ptak
A
A
Rahmouni
K
K
Mazeau
N T
NT
Thuong
M
M
Leng
D002942:Circular Dichroism; D002945:Cisplatin / Q000032:analysis*; D006859:Hydrogen; D009682:Magnetic Resonance Spectroscopy; D015394:Molecular Structure; D009838:Oligodeoxyribonucleotides / Q000032:analysis*; D010758:Phosphorus; D013056:Spectrophotometry, Ultraviolet
D009838:Oligodeoxyribonucleotides; D010758:Phosphorus; D006859:Hydrogen; D002945:Cisplatin