title: A study of the oxidized form of Pseudomonas aeruginosa cytochrome c-551 peroxidase with the use of magnetic circular dichroism.
abstract: The magnetic properties at different temperatures of oxidized Pseudomonas aeruginosa cytochrome c-551 peroxidase were studied, with the use of the technique of magnetic-circular-dichroism spectroscopy. At 4.2K, both constituent haems were found to be low-spin, and the axial ligand pairs were identified as histidine-histidine and histidine-methionine. At room temperature high-spin signals were observed, amounting to less than 25% of the total haem present. These signals are concluded to arise mainly from a temperature-dependent spin-state equilibrium in the methionine-ligated haem.
mesh_terms: D001426:Bacterial Proteins; D002942:Circular Dichroism; D003574:Cytochrome c Group; D003578:Cytochrome-c Peroxidase; D003901:Desulfovibrio / Q000032:analysis; D004578:Electron Spin Resonance Spectroscopy; D006418:Heme / Q000032:analysis; D008280:Magnetics; D010084:Oxidation-Reduction; D010544:Peroxidases; D011550:Pseudomonas aeruginosa / Q000201:enzymology*; D013696:Temperature
chemical_list: D001426:Bacterial Proteins; D003574:Cytochrome c Group; D006418:Heme; C017165:cytochrome c(3); C017167:cytochrome C(551); D010544:Peroxidases; D003578:Cytochrome-c Peroxidase