title: Time-resolved step-scan Fourier transform infrared investigation of heme-copper oxidases: implications for O2 input and H2O/H+ output channels.
abstract: We have applied FTIR and time-resolved step-scan Fourier transform infrared (TRS(2)-FTIR) spectroscopy to investigate the dynamics of the heme-Cu(B) binuclear center and the protein dynamics of mammalian aa(3), Pseudomonas stutzeri cbb(3), and caa(3) and ba(3) from Thermus thermophilus cytochrome oxidases. The implications of these results with respect to (1) the molecular motions that are general to the photodynamics of the binuclear center in heme-copper oxidases, and (2) the proton pathways located in the ring A propionate of heme a(3)-Asp372-H(2)O site that is conserved among all structurally known oxidases are discussed.
authors.affiliation: Department of Chemistry, University of Crete, 71409 Heraklion, Crete, Greece.
authors.forename: Constantinos
authors.initials: C
authors.lastname: Koutsoupakis
authors.forename: Eftychia
authors.initials: E
authors.lastname: Pinakoulaki
authors.forename: Stavros
authors.initials: S
authors.lastname: Stavrakis
authors.forename: Vangelis
authors.initials: V
authors.lastname: Daskalakis
authors.forename: Constantinos
authors.initials: C
authors.lastname: Varotsis
mesh_terms: D000818:Animals; D002417:Cattle; D003573:Cytochrome b Group / Q000737:chemistry / Q000378:metabolism; D003574:Cytochrome c Group / Q000737:chemistry / Q000378:metabolism; D045264:Cytochromes a / Q000737:chemistry / Q000378:metabolism; D045266:Cytochromes a3 / Q000737:chemistry / Q000378:metabolism; D003576:Electron Transport Complex IV / Q000737:chemistry* / Q000378:metabolism*; D066298:In Vitro Techniques; D008958:Models, Molecular; D010100:Oxygen / Q000378:metabolism; D018892:Proton-Motive Force; D044223:Pseudomonas stutzeri / Q000201:enzymology; D017550:Spectroscopy, Fourier Transform Infrared; D016963:Thermus thermophilus / Q000201:enzymology; D014867:Water / Q000378:metabolism
chemical_list: D003573:Cytochrome b Group; D003574:Cytochrome c Group; D045266:Cytochromes a3; C435384:cytochrome caa(3); D014867:Water; D045264:Cytochromes a; C058557:cytochrome ba3; C414443:cbb3 oxidase; D003576:Electron Transport Complex IV; D010100:Oxygen