The inhibitory binding site(s) of Zn2+ in cytochrome c oxidase.
EXAFS analysis of Zn binding site(s) in bovine-heart cytochrome c oxidase and characterization of the inhibitory effect of internal zinc on respiratory activity and proton pumping of the liposome reconstituted oxidase are presented. EXAFS identifies tetrahedral coordination site(s) for Zn(2+) with two N-histidine imidazoles, one N-histidine imidazol or N-lysine and one O-COOH (glutamate or aspartate), possibly located at the entry site of the proton conducting D pathway in the oxidase and involved in inhibition of the oxygen reduction catalysis and proton pumping by internally trapped zinc.
Francia
Francesco
F
Department of Biology, University of Bologna, Bologna, Italy.
Giachini
Lisa
L
Boscherini
Federico
F
Venturoli
Giovanni
G
Capitanio
Giuseppe
G
Martino
Pietro Luca
PL
Papa
Sergio
S
D000818:Animals; D001665:Binding Sites / Q000187:drug effects; D002417:Cattle; D002462:Cell Membrane / Q000187:drug effects / Q000201:enzymology; D004579:Electron Transport / Q000187:drug effects; D003576:Electron Transport Complex IV / Q000037:antagonists & inhibitors* / Q000737:chemistry* / Q000378:metabolism; D006736:Horses; D008081:Liposomes; D008958:Models, Molecular; D021122:Protein Subunits / Q000737:chemistry / Q000378:metabolism; D017494:Proton Pumps / Q000187:drug effects; D011522:Protons; D015032:Zinc / Q000378:metabolism* / Q000494:pharmacology*
D008081:Liposomes; D021122:Protein Subunits; D017494:Proton Pumps; D011522:Protons; D003576:Electron Transport Complex IV; D015032:Zinc