title: The origin of the Fe(IV)=O intermediates in cytochrome aa(3) oxidase.
abstract: The dioxygen reduction mechanism in cytochrome oxidases relies on proton control of the electron transfer events that drive the process. Proton delivery and proton channels in the protein that are relevant to substrate reduction and proton pumping are considered, and the current status of this area is summarized. We propose a mechanism in which the coupling of the oxygen reduction chemistry to proton translocation (P→F transition) is related to the properties of two groups of highly conserved residues, namely, His411/G386-T389 and the heme a(3)-propionateA-D399-H403 chain.
authors.affiliation: Department of Chemistry, University of Cyprus, Nicosia, Cyprus.
authors.forename: Eftychia
authors.initials: E
authors.lastname: Pinakoulaki
authors.forename: Vangelis
authors.initials: V
authors.lastname: Daskalakis
authors.forename: Constantinos
authors.initials: C
authors.lastname: Varotsis
mesh_terms: D001412:Bacillus subtilis / Q000201:enzymology / Q000378:metabolism; D001426:Bacterial Proteins / Q000737:chemistry / Q000378:metabolism; D001665:Binding Sites; D001692:Biological Transport; D004579:Electron Transport; D003576:Electron Transport Complex IV / Q000737:chemistry* / Q000378:metabolism; D005290:Ferric Compounds / Q000737:chemistry / Q000378:metabolism; D006418:Heme / Q000031:analogs & derivatives / Q000737:chemistry / Q000378:metabolism; D006639:Histidine / Q000737:chemistry / Q000378:metabolism; D006861:Hydrogen Peroxide / Q000737:chemistry* / Q000378:metabolism; D007501:Iron / Q000737:chemistry* / Q000378:metabolism; D008956:Models, Chemical; D008958:Models, Molecular; D015394:Molecular Structure; D010084:Oxidation-Reduction; D010100:Oxygen / Q000737:chemistry* / Q000378:metabolism; D011487:Protein Conformation; D011522:Protons; D013059:Spectrum Analysis, Raman
chemical_list: D001426:Bacterial Proteins; D005290:Ferric Compounds; D011522:Protons; C027728:heme a; D006418:Heme; D006639:Histidine; D006861:Hydrogen Peroxide; D007501:Iron; D003576:Electron Transport Complex IV; D010100:Oxygen