OXPHOS capacity

high-resolution terminology - matching measurements at high-resolution

OXPHOS capacity

Description

OXPHOS capacity (P; compare State 3) is the respiratory capacity of mitochondria in the ADP-activated state of oxidative phosphorylation, at saturating concentrations of ADP, inorganic phosphate, oxygen, and defined reduced substrates. Since OXPHOS is partially coupled, intrinsic uncoupling and dyscoupling contribute to the control of flux in the OXPHOS state (state P). OXPHOS capacity is expressed (i) per mt-marker (O₂ flux per mt-protein, CS, etc); if ETS capacity, E, is used as a functional mitochondrial marker, then OXPHOS capacity is expressed as the P/E ratio (flux control ratio). (ii) OXPHOS capacity is expressed per tissue or cell mass, integrating mt-quantity (density) and mt-quality (O₂ flux). (iii) OXPHOS capacity is expressed per cell (O₂ flow), which then is a function of mt-density, mt-quality, and cell size.

Abbreviation: P

Reference: Gnaiger 2012 MitoPathways, Gnaiger 2009 Int J Biochem Cell Biol

File:OXPHOS.png

Coupled energy cycles of oxidative phosphorylation stimulated by saturating concentrations of ADP and inorganic phosphate. 2[H] indicates the reduced hydrogen equivalents of CHO substrates and electron transfer to oxygen. H⁺_out are protons pumped out of the matrix phase to the positive P-phase. Proton flow to the negative matrix phase (H⁺_in) drives the phosphorylation of ADP to ATP. The capacity of the phosphorylation system may contribute to the limitation of flux. Proton leaks dissipate energy of translocated protons from low pH in the positive P-phase to the negative N-phase (modified after Gnaiger 2012 MitoPathways).

MitoPedia methods: Respirometry 

MitoPedia topics: "Respiratory state" is not in the list (Enzyme, Medium, Inhibitor, Substrate and metabolite, Uncoupler, Sample preparation, Permeabilization agent, EAGLE, MitoGlobal Organizations, MitoGlobal Centres, ...) of allowed values for the "MitoPedia topic" property. Respiratory state"Respiratory state" is not in the list (Enzyme, Medium, Inhibitor, Substrate and metabolite, Uncoupler, Sample preparation, Permeabilization agent, EAGLE, MitoGlobal Organizations, MitoGlobal Centres, ...) of allowed values for the "MitoPedia topic" property. 

Related terms in Bioblast

LEAK, L

ROUTINE, R

OXPHOS, P

ETS, E

ROX, R