Far Ultraviolet Resonance Raman Spectroscopy of Proteins and Protein Components
Recent advances in laser technology offer an opportunity to exploit the resonance Raman effect using far ultraviolet excitation wavelengths (down to 200nm). Detailed vibrational information can now be obtained on ultraviolet chromophores within protein selectively. We have concentrated attention on the aromatic amino acids, and amide chromophores. Data are presented for tyrosine, tryptophan, and phenylalanine at varying excitation wavelength, and under different conditions (H2O, D2O, and high pH). Within proteins, environmentally sensitive amide, tyrosine, and tryptophan modes serve as markers of secondary structure, and solvent accessibility of particular protein segments. Data are presented for hemoglobin, cytochrome c, and the abnormal tyrosine residue of chicken ovomucoid domain III.