Interactions of water-soluble metalloporphyrins with nucleic acids studied by resonance Raman spectroscopy.
The resonance Raman spectra of water-soluble porphyrins, M(TMpy-P4) (M = Cu(II), Ni(II) and Co(III] and their mixtures with poly(dG-dC)2, poly(dA-dT)2 and calf thymus and salmon DNAs were measured using a divided rotating cell to determine the magnitudes of frequency shift and intensity variation resulting from M(TMpy-P4)-nucleic acid interactions. Bands II(C beta-H bending, approximately 1100 cm-1) and VIII(C beta-C beta stretch, approximately 1570 cm-1) show a large and small upward shift, respectively, when Cu(TMpy-P4) and Ni(TMpy-P4) are intercalated at the G-C sites. In contrast, these bands show a small upward and downward shift, respectively, when Co(TMpy-P4) is groove-bound at the A-T sites of nucleic acids. Both Bands V (approximately 1260 cm-1) and IX (approximately 1646 cm-1) which originate in the N-methylpyridyl group always show small downward shifts due to coulombic interaction between the N-CH3+ group of TMpy-P4 and the PO2 group of the nucleic acid.
Schneider
J H
JH
Marquette University, Milwaukee, WI 53233.
Odo
J
J
Nakamoto
K
K
D003035:Cobalt; D003300:Copper; D004247:DNA; D017324:Hematoporphyrin Derivative; D006415:Hematoporphyrins; D008665:Metalloporphyrins; D009532:Nickel; D011089:Polydeoxyribonucleotides; D013056:Spectrophotometry, Ultraviolet; D013059:Spectrum Analysis, Raman / Q000379:methods
D006415:Hematoporphyrins; D008665:Metalloporphyrins; D011089:Polydeoxyribonucleotides; D003035:Cobalt; D017324:Hematoporphyrin Derivative; D003300:Copper; D009532:Nickel; D004247:DNA