[Interaction of Ag+ ions with DNA and its monomers].
Differential UV spectra of DNA and its monomers that were induced by Ag+ ions were measured, and the effect of ions on the parameters of the helix-coil transition was studied. The data obtained confirm the existence of "strong" and "weak" modes of binding of Ag+ to DNA. The earlier proposed proton transfer from N1G to N3C, which is determined by the interaction of Ag+ with N7G (a "strong" complex), follows immediately from the shape of the differential UV spectra. The positive cooperativity of the binding of Ag+ to DNA upon the formation of a "weak" complex is due to the cooperativity of the transition of DNA to a new double-helical conformation. A model of this conformation is proposed which suggests the formation of Hougsteen GC and AT pairs.
Sorokin
V A
VA
Verkin Physicotechnical Institute of Low Temperatures, National Academy of Sciences of Ukaine, Kharkov, Ukraine.
Valeev
V A
VA
Gladchenko
G O
GO
Sysa
I V
IV
Volchok
I V
IV
Blagoĭ
Iu P
IuP
D002414:Cations, Monovalent; D004247:DNA / Q000737:chemistry*; D012834:Silver / Q000737:chemistry*; D013056:Spectrophotometry, Ultraviolet
D002414:Cations, Monovalent; D012834:Silver; D004247:DNA