Resonance Raman spectra of iron(III)-, copper(II)-, cobalt(III)-, and manganese(III)-transferrins and of bis(2,4,6-trichlorophenolato)diimidazolecopper(II) monohydrate, a possible model for copper(II) binding to transferrins
Autor: | James R. Scherer, Saima Kint, Yoshio Tomimatsu |
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Rok vydání: | 1976 |
Předmět: |
Protein Conformation
Iron Inorganic chemistry chemistry.chemical_element Manganese Spectrum Analysis Raman Biochemistry symbols.namesake Organometallic Compounds Moiety Binding Sites Ligand Lasers Transferrin Resonance Cobalt Copper Crystallography Models Chemical chemistry Spectrophotometry Molecular vibration symbols Spectrophotometry Ultraviolet Raman spectroscopy Protein Binding |
Zdroj: | Biochemistry. 15:4918-4924 |
ISSN: | 1520-4995 0006-2960 |
DOI: | 10.1021/bi00667a026 |
Popis: | Fe(III), Cu(II), Co(III), and Mn(III) complexes of ovo- and human serum transferrins show resonance enhanced Raman bands near 1600, 1500, 1270, and 1170 cm-1 upon excitation with laser frequencies which fall within the visible absorption bands of those metalloproteins. Comparison of the visible absorption and resonance Raman spectra of the Cu(II)-transferrin complexes with those for the Cu(II) model compound, bis(2,4,6-trichlorophenolato)diimidazolecopper(II) monohydrate, indicates that the resonance Raman bands are due to enhancement of phenolic vibrational modes. For the model (Cu(II) compound, a normal coordinate analysis was used to aid our assignment of the observed resonance bands at 1562, 1463, 1311, and 1122 cm-1 to A1 vibrational modes of the 2,4,6-trichlorophenolato moiety. These assignments are consistent with those made for Cu(II)-transferrins. The latter assignments were based upon calculated A1 frequencies for p-methylphenol (Cummings, D.L., and Wood, J.L. (1974), J. Mol. Struct. 20, 1). The wavelength shifts in the resonance bands for the model compound from those for Cu(II)-transferrins are due to the influence of the chloro substituents on the planar vibrations of phenol. These results clearly identify tyrosine as a ligand in copper binding to transferrins. |
Databáze: | OpenAIRE |
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