title: Resonance Raman characterization of a novel, oxygen-binding heme protein from Chromatium vinosum.
abstract: Resonance Raman spectroscopy was employed to characterize the local heme environment of a high-spin, ligand-binding heme protein from Chromatium vinosum (Chromatium high-spin hemoprotein). High-frequency spectra obtained with both B- and Q-band excitation were found to resemble qualitatively those of deoxyhemoglobin (HbA). Differences between HbA and Chromatium high-spin hemoprotein spectra can be assigned to either the effects of a covalent linkage of the heme vinyls to the protein matrix or alterations in the heme-proximal ligand bonding interaction. Both kinematic and electronic effects were evident. The behavior of heme core-size sensitive modes and low-frequency modes in Chromatium high-spin hemoprotein may be an indication of distortions in the heme geometry of Chromatium high-spin hemoprotein relative to HbA. The effects of covalent bonding of the heme peripheral vinyls upon the vibrational, electronic, and geometric characteristics of the heme active site in Chromatium high-spin hemoprotein are discussed.
mesh_terms: D002844:Chromatium / Q000032:analysis*; D006420:Hemeproteins / Q000378:metabolism; D006441:Hemoglobin A; D006454:Hemoglobins; D010100:Oxygen / Q000378:metabolism*; D013059:Spectrum Analysis, Raman
chemical_list: D006420:Hemeproteins; D006454:Hemoglobins; C100003:deoxyhemoglobin; D006441:Hemoglobin A; D010100:Oxygen