Particular behavior of the adenine and guanine ring-breathing modes upon the DNA conformational transitions.
Harmonic dynamics calculations performed on the deoxyguanosine (dG) and deoxyadenosine (dA) residues, based on a reliable force field, show that the breathing motions of both guanine and adenine residues are involved in two different vibration modes (750-500 cm-1 spectral region). The calculated results reveal a strong coupling of these modes with the sugar pucker motions. This effect has been verified for the dG residue by the Raman spectra of polyd(G-C). As far as the dA residue is concerned, the particular behavior of the adenine residue breathing mode predicted by these calculations, has been confirmed by Raman spectra of polyd(A-T) undergoing a B----Z conformational transition.
D000225:Adenine; D055598:Chemical Phenomena; D002621:Chemistry; D004247:DNA; D006147:Guanine; D009690:Nucleic Acid Conformation; D013059:Spectrum Analysis, Raman; D014732:Vibration
D006147:Guanine; D004247:DNA; D000225:Adenine