title: Diheme cytochrome c-554 from Nitrosomonas. Soret resonance Raman indication of an unusual ferric 5-coordinate structure.
abstract: The diheme cytochrome c-554 which participates in ammonia oxidation in the chemoautotroph , Nitrosomonas europaea has been studied by Soret excitation resonance Raman spectroscopy. The Raman spectrum of reduced cytochrome c-554 at neutral pH is similar classical 6-coordinate low-spin ferrous mammalian cytochrome c. In contrast, the spectrum of ferric cytochrome c-554 suggests a 5-coordinate state which is unusual for c hemes. The oxidized spectrum closely resemble that of horseradish peroxidase (HRP) or cytochrome c peroxidase (CcP) at pH 6.4. The narrow linewidth of the heme core-size vibrations indicates that both heme irons of c-554 have similar geometries.
mesh_terms: D003574:Cytochrome c Group; D006418:Heme; D006863:Hydrogen-Ion Concentration; D009606:Nitrosomonas / Q000032:analysis*; D010084:Oxidation-Reduction; D013059:Spectrum Analysis, Raman
chemical_list: D003574:Cytochrome c Group; C083951:cytochrome c553; D006418:Heme; C022302:cytochrome C-552