title: Functional proton transfer pathways in the heme-copper oxidase superfamily.
abstract: Heme-copper oxidases (HCuOs) terminate the respiratory chain in mitochondria and most bacteria. They are transmembrane proteins that catalyse the reduction of oxygen and use the liberated free energy to maintain a proton-motive force across the membrane. The HCuO superfamily has been divided into the oxygen-reducing A-, B- and C-type oxidases as well as the bacterial NO reductases (NOR), catalysing the reduction of NO in the denitrification process. Proton transfer to the catalytic site in the mitochondrial-like A family occurs through two well-defined pathways termed the D- and K-pathways. The B, C, and NOR families differ in the pathways as well as the mechanisms for proton transfer to the active site and across the membrane. Recent structural and functional investigations, focussing on proton transfer in the B, C and NOR families will be discussed in this review.
authors: Department of Biochemistry and Biophysics, Stockholm University, Stockholm, Sweden.
authors: Hyun Ju
authors: HJ
authors: Lee
authors: Joachim
authors: J
authors: Reimann
authors: Yafei
authors: Y
authors: Huang
authors: Pia
authors: P
authors: Adelroth
mesh_terms: D001426:Bacterial Proteins / Q000737:chemistry / Q000378:metabolism; D001692:Biological Transport; D020134:Catalytic Domain; D006418:Heme / Q000737:chemistry / Q000378:metabolism*; D007700:Kinetics; D008958:Models, Molecular; D010084:Oxidation-Reduction; D010088:Oxidoreductases / Q000737:chemistry / Q000145:classification / Q000378:metabolism*; D017494:Proton Pumps / Q000737:chemistry / Q000378:metabolism*; D011522:Protons
chemical_list: D001426:Bacterial Proteins; D017494:Proton Pumps; D011522:Protons; D006418:Heme; D010088:Oxidoreductases; C024748:copper oxidase