F-to-O transition of cytochrome c oxidase: pH and temperature effects on the kinetics of charge translocation

2000 ◽  
Vol 28 (5) ◽  
pp. A469-A469 ◽  
Author(s):  
S. Siletsky ◽  
D. Zaslavsky ◽  
I. Smirnova ◽  
A. Kaulen ◽  
A. Konstantinov
Keyword(s):  
Cytochrome C ◽  
Cytochrome C Oxidase ◽  
Temperature Effects ◽  
Charge Translocation ◽  
Kinetics Of

scholarly journals Proton and electrical charge translocation by cytochrome-c oxidase

1997 ◽  
Vol 1318 (1-2) ◽  
pp. 299-306 ◽  
Author(s):  
Mårten Wikström ◽  
Joel E Morgan ◽  
Michael I Verkhovsky
Keyword(s):  
Cytochrome C ◽  
Cytochrome C Oxidase ◽  
Electrical Charge ◽  
Charge Translocation

scholarly journals Reaction of S. cerevisiae mitochondria with ligands: Kinetics of CO and O 2 binding to flavohemoglobin and cytochrome c oxidase

2017 ◽  
Vol 1858 (2) ◽  
pp. 182-188 ◽  
Author(s):  
Markus L. Björck ◽  
Shu Zhou ◽  
Camilla Rydström Lundin ◽  
Martin Ott ◽  
Pia Ädelroth ◽  
...  
Keyword(s):  
Cytochrome C ◽  
Cytochrome C Oxidase ◽  
Kinetics Of

scholarly journals Kinetic studies on the reaction between cytochrome c oxidase and ferrocytochrome c

1975 ◽  
Vol 147 (1) ◽  
pp. 145-153 ◽  
Author(s):  
M T Wilson ◽  
C Greenwood ◽  
M Brunori ◽  
E Antonini
Keyword(s):  
Cytochrome C ◽  
Cytochrome C Oxidase ◽  
Time Course ◽  
Kinetic Studies ◽  
Initial Reaction ◽  
Fast Phase ◽  
Ferrocytochrome C ◽  
Cytochrome C2 ◽  
Kinetics Of ◽  
Flow Experiments

In stopped-flow experiments in which oxidized cytochrome c oxidase was mixed with ferrocytochrome c in the presence of a range of oxygen concentrations and in the absence and presence of cyanide, a fast phase, reflecting a rapid approach to an equilibrium, was observed. Within this phase, one or two molecules of ferrocytochrome were oxidized per haem group of cytochrome a, depending on the concentration of ferrocytochrome c used. The reasons for this are discussed in terms of a mechanism in which all electrons enter through cytochrome a, which, in turn, is in rapid equilibrium with a second site, identified with ‘visible’ copper (830 nm-absorbing) Cud (Beinert et al., 1971). The value of the bimolecular rate constant for the reaction between cytochromes c2+ and a3+ was between 10(6) and 10(7) M(-1)-S(-1); some variability from preparation to preparation was observed. At high ferrocytochrome c concentrations, the initial reaction of cytochrome c2+ with cytochrome a3+ could be isolated from the reaction involving the ‘visible’ copper and the stoicheiometry was found to approach one molecule of cytochrome c2+ oxidized for each molecule of cytochrome a3+ reduced. At low ferrocytochrome c concentrations, however, both sites (i.e. cytochrome a and Cud) were reduced simultaneously and the stoicheiometry of the initial reaction was closer to two molecules of cytochrome c2+ oxidized per molecule of cytochrome a reduced. The bleaching of the 830 nm band lagged behind or was simultaneous with the formation of the 605 nm band and does not depend on the cytochrome c concentration, whereas the extinction at the steady-state does. The time-course of the return of the 830 nm-absorbing species is much faster than the bleaching of the 605 nm-absorbing component, and parallels that of the turnover phase of cytochrome c2+ oxidation. Additions of cyanide to the oxidase preparations had no effect on the observed stoicheiometry or kinetics of the reduction of cytochrome a and ‘visible’ copper, but inhibited electron transfer to the other two sites, cytochrome a3 and the undetectable copper, Cuu.

scholarly journals Altered kinetics of cytochrome c oxidase in a patient with severe mitochondrial encephalomyopathy

1995 ◽  
Vol 1270 (2-3) ◽  
pp. 193-201 ◽  
Author(s):  
Leo G.J. Nijtmans ◽  
Peter G. Barth ◽  
Carsten R. Lincke ◽  
Mieke J.M. Van Galen ◽  
Rob Zwart ◽  
...  
Keyword(s):  
Cytochrome C ◽  
Cytochrome C Oxidase ◽  
Mitochondrial Encephalomyopathy ◽  
Kinetics Of
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