Difference between revisions of "E-R control efficiency"
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|abbr=''j<sub>E-R</sub>'' | |abbr=''j<sub>E-R</sub>'' | ||
|description=[[Image:jExR.jpg|50 px|ET-reserve control efficiency]] The apparent '''ET-reserve control efficiency''' (''E-R'' control efficiency), ''j<sub>E-R</sub>'' = (''E-R'')/''E'' = 1-''R/E'', is an expression of the relative scope of increasing [[ROUTINE respiration]] in living cells by uncoupling. ''j<sub>E-R</sub>'' = 0.0 for zero excess capacity when ''R''=''E''; ''j<sub>E-R</sub>'' = 1.0 for the maximum limit when ''R''=0. The [[ROUTINE]] state of living cells is stimulated to [[electron transfer pathway]] by [[uncoupler]] titration, which yields the [[ET-reserve capacity]] ''E-R''. Since ET-capacity is significantly higher than OXPHOS capacity in various cell types (as shown by '''[[cell ergometry]]'''), ''j<sub>E-R</sub>'' is not a reserve capacity available for the cell to increase oxidative phosphorylation, but strictly a scope (reserve) for uncoupling respiration. Similarly, the apparent [[ET-excess capacity]] ''E-P'' is not a respiratory reserve in the sense of oxidative phosphorylation. | |description=[[Image:jExR.jpg|50 px|ET-reserve control efficiency E-R]] The apparent '''ET-reserve control efficiency E-R''' (''E-R'' control efficiency), ''j<sub>E-R</sub>'' = (''E-R'')/''E'' = 1-''R/E'', is an expression of the relative scope of increasing [[ROUTINE-respiration]] in living cells by uncoupling. ''j<sub>E-R</sub>'' = 0.0 for zero excess capacity when ''R''=''E''; ''j<sub>E-R</sub>'' = 1.0 for the maximum limit when ''R''=0. The [[ROUTINE]]-state of living cells is stimulated to [[electron transfer pathway]] by [[uncoupler]] titration, which yields the [[ET-reserve capacity]] ''E-R''. Since ET-capacity is significantly higher than OXPHOS-capacity in various cell types (as shown by '''[[cell ergometry]]'''), ''j<sub>E-R</sub>'' is not a reserve capacity available for the cell to increase oxidative phosphorylation, but strictly a scope (reserve) for uncoupling respiration. Similarly, the apparent [[ET-excess capacity]] ''E-P'' is not a respiratory reserve in the sense of oxidative phosphorylation. | ||
|info=[[Flux control efficiency]] | |info=[[Flux control efficiency]] | ||
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== Keywords == | |||
{{Template:Keywords: Coupling control}} | |||
{{MitoPedia concepts | {{MitoPedia concepts |
Revision as of 04:23, 9 November 2020
Description
The apparent ET-reserve control efficiency E-R (E-R control efficiency), jE-R = (E-R)/E = 1-R/E, is an expression of the relative scope of increasing ROUTINE-respiration in living cells by uncoupling. jE-R = 0.0 for zero excess capacity when R=E; jE-R = 1.0 for the maximum limit when R=0. The ROUTINE-state of living cells is stimulated to electron transfer pathway by uncoupler titration, which yields the ET-reserve capacity E-R. Since ET-capacity is significantly higher than OXPHOS-capacity in various cell types (as shown by cell ergometry), jE-R is not a reserve capacity available for the cell to increase oxidative phosphorylation, but strictly a scope (reserve) for uncoupling respiration. Similarly, the apparent ET-excess capacity E-P is not a respiratory reserve in the sense of oxidative phosphorylation.
Abbreviation: jE-R
Reference: Flux control efficiency
Keywords
4-compartmental OXPHOS model. (1) ET capacity E of the noncoupled electron transfer system ETS. OXPHOS capacity P is partitioned into (2) the dissipative LEAK component L, and (3) ADP-stimulated P-L net OXPHOS capacity. (4) If P-L is kinetically limited by a low capacity of the phosphorylation system to utilize the protonmotive force pmF, then the apparent E-P excess capacity is available to drive coupled processes other than phosphorylation P» (ADP to ATP) without competing with P».
- Bioblast links: Coupling control - >>>>>>> - Click on [Expand] or [Collapse] - >>>>>>>
1. Mitochondrial and cellular respiratory rates in coupling-control states
Respiratory rate | Defining relations | Icon | |
---|---|---|---|
OXPHOS capacity | P = P´-Rox | mt-preparations | |
ROUTINE respiration | R = R´-Rox | living cells | |
ET capacity | E = E´-Rox | » Level flow | |
» Noncoupled respiration - Uncoupler | |||
LEAK respiration | L = L´-Rox | » Static head | |
» LEAK state with ATP | |||
» LEAK state with oligomycin | |||
» LEAK state without adenylates | |||
Residual oxygen consumption Rox | L = L´-Rox |
2. Flux control ratios related to coupling in mt-preparations and living cells
FCR | Definition | Icon | |
---|---|---|---|
L/P coupling-control ratio | L/P | » Respiratory acceptor control ratio, RCR = P/L | |
L/R coupling-control ratio | L/R | ||
L/E coupling-control ratio | L/E | » Uncoupling-control ratio, UCR = E/L (ambiguous) | |
P/E control ratio | P/E | ||
R/E control ratio | R/E | » Uncoupling-control ratio, UCR = E/L | |
net P/E control ratio | (P-L)/E | ||
net R/E control ratio | (R-L)/E |
3. Net, excess, and reserve capacities of respiration
Respiratory net rate | Definition | Icon |
---|---|---|
P-L net OXPHOS capacity | P-L | |
R-L net ROUTINE capacity | R-L | |
E-L net ET capacity | E-L | |
E-P excess capacity | E-P | |
E-R reserve capacity | E-R |
4. Flux control efficiencies related to coupling-control ratios
Coupling-control efficiency | Definition | Icon | Canonical term | ||
---|---|---|---|---|---|
P-L control efficiency | jP-L | = (P-L)/P | = 1-L/P | P-L OXPHOS-flux control efficiency | |
R-L control efficiency | jR-L | = (R-L)/R | = 1-L/R | R-L ROUTINE-flux control efficiency | |
E-L coupling efficiency | jE-L | = (E-L)/E | = 1-L/E | E-L ET-coupling efficiency » Biochemical coupling efficiency | |
E-P control efficiency | jE-P | = (E-P)/E | = 1-P/E | E-P ET-excess flux control efficiency | |
E-R control efficiency | jE-R | = (E-R)/E | = 1-R/E | E-R ET-reserve flux control efficiency |
5. General
- » Basal respiration
- » Cell ergometry
- » Dyscoupled respiration
- » Dyscoupling
- » Electron leak
- » Electron-transfer-pathway state
- » Hyphenation
- » Oxidative phosphorylation
- » Oxygen flow
- » Oxygen flux
- » Permeabilized cells
- » Phosphorylation system
- » Proton leak
- » Proton slip
- » Respiratory state
- » Uncoupling
MitoPedia concepts:
Respiratory control ratio