- high-resolution terminology - matching measurements at high-resolution
Q-pools
Description
Different Q-pools are more or less clearly distinguished in the cell, related to a variety of models describing degress of Q-pool behavior. (1) CoQ-pools are distinguished according to their compartmentation in the cell: mitochondrial CoQ (mtCoQ) and CoQ in other organelles versus plasma-membrane CoQ. (2) The total mitochondrial CoQ-pool mtCoQ is partitioned into an ETS-reactive Q-pool, Qra, and an inactive mtCoQ-pool, Qia. (2a) The Qra-pool is fully reduced in the form of quinol QH2 under anoxia, fully oxidized in the form of quinone in aerobic mitochondrial preparations incubated without CHNO-fuel substrates, and intermediate redox states of Qra are sensitive to pathway control and coupling control of mitochondrial electron transfer and OXPHOS. (2b) The Qia-pool remains partially reduced and oxidized in aerob-anoxic transitions and is insensitive to mitochondrial respiratory states. (3) The Qra-pool is partitioned into Q with Q-pool behavior according to the fluid-state model (synonymous: random-collision model) and Q tightly bound to supercomplexes according to the solid-state model. The two models describe the extremes in a continuum of homogenous or heterogenous Q-pool behavior. The CII-Q-CIII segment of the S-pathway is frequently considered to follow homogenous Q-pool behavior participating in the Qhom-pool, whereas the CI-Q-CIII segment of the N-pathway indicates supercomplex organization with different degrees of Q-pool heterogeneity contributing to the Qhet-pool with metabolic channeling.
Abbreviation: Q
Reference: Komlodi 2021 MitoFit Q
Communicated by Gnaiger Erich 2021-04-03
| Q-pool | Symbol | Definition | Balance |
|---|---|---|---|
| Coenzyme Q | CoQ | total CoQ in the cell | |
| mitochondrial CoQ | mtCoQ | total CoQ in mitochondria | mtCoQ = Qra + Qia |
| inactive mtCoQ | Qia | inactive mitochondrial CoQ, paritally oxidized under anoxia and partially reduced in aerobic mt-preparations incubated without CHNO-fuel substrates | |
| ETS-reactive Q | Qra = Q | Electron-transfer-system reactive mtCoQ, fully reduced under anoxia, fully oxidized in aerobic mt-preparations incubated without CHNO-fuel substrates | Q = Qhom + Qhet |
| homogenous Q | Qhom | homogenous pool of ETS-reactive Q according to the fluid-state model (random collision model) | |
| heterogenous Q | Qhet | heterogenous pool of ETS-reactive Q according to the solid-state model |
Keywords
- Bioblast links: Q - >>>>>>> - Click on [Expand] or [Collapse] - >>>>>>>
- Coenzyme Q
- » Coenzyme Q
- » Quinone, Ubiquinone Q; oxidized
- » Quinol, Ubiquinol QH2; reduced
- » Semiquinone
- » Coenzyme Q2
- » Q-redox state
- » Q-pools
- Coenzyme Q
- Mitochondrial pathways, respiratory Complexes, and Q
- » Q-cycle
- » Q-junction
- » Convergent electron flow
- » NS-pathway
- » FNS
- » FNSGp
- Mitochondrial pathways, respiratory Complexes, and Q
- NextGen-O2k and Q-Module
The Q-Module is part of the NextGen-O2k project
- The Q-Module allows for monitoring of the redox state of electron transfer-reactive coenzyme Q at the Q-junction using the specific Q-Stoppers with the integrated three-electrode system and the modified electronics of the NextGen-O2k. Cyclic voltammetry is used for quality control and for defining the polarization voltage applied during Q-redox measurements.
- Reference:
- Komlódi T, Cardoso LHD, Doerrier C, Moore AL, Rich PR, Gnaiger E (2021) Coupling and pathway control of coenzyme Q redox state and respiration in isolated mitochondria. Bioenerg Commun 2021.3. https://doi.org/10.26124/bec:2021-0003
- Reference:
MitoPedia concepts:
MiP concept
MitoPedia topics:
Substrate and metabolite
