Difference between revisions of "P-L net OXPHOS capacity"

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P-L net OXPHOS capacity

Description

The P-L net OXPHOS capacity is the OXPHOS capacity corrected for LEAK respiration. P-L is the scope for ADP stimulation, the respiratory capacity potentially available for phosphorylation of ADP to ATP. Oxygen consumption in the OXPHOS state, therefore, is partitioned into P-L, strictly coupled to phosphorylation P», and nonphosphorylating LEAK respiration, L_P, compensating for proton leaks, slip and cation cycling: P = P-L+L_P. It is frequently assumed that LEAK respiration L as measured in the LEAK state, overestimates the LEAK component of respiration, L_P, as measured in the OXPHOS state, particularly if the protonmotive force is not adjusted to equivalent levels in L and L_P. However, if the LEAK component increases with enzyme turnover during P, the low enzyme turnover during L may counteract the effect of the higher pmF.

Abbreviation: P-L

Reference: Gnaiger 2020 BEC MitoPathways

Communicated by Gnaiger E (2014-08-09) last update 2020-11-11

Keywords

Expand Bioblast links to P-L net OXPHOS capacity

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The Blue Book 2020
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OXPHOS-, ROUTINE-, ET-, and LEAK states; respiratory capacities (P, R, E, L) corrected for residual oxygen consumption Rox.
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».
(P-L)/P is the OXPHOS P-L control efficiency. The biochemical coupling efficiency is independent of kinetic control by the phosphorylation system when expressed as the E-L coupling efficiency, (E-L)/E. (E-P)/E is the kinetic E-P control efficiency.

Bioblast links: Coupling control - >>>>>>> - Click on [Expand] or [Collapse] - >>>>>>>

1. Mitochondrial and cellular respiratory rates in coupling-control states

» Baseline state

Respiratory rate	Defining relations
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

Chance and Williams nomenclature: respiratory states

» State 1 —» State 2 —» State 3 —» State 4 —» State 5

2. Flux control ratios related to coupling in mt-preparations and living cells

» Flux control ratio

» Coupling-control ratio

» Coupling-control protocol

FCR	Definition
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

» Flux control efficiency j_Z-Y

» Background state

» Reference state

» Metabolic control variable

Coupling-control efficiency		Definition		Canonical term
P-L control efficiency	j_P-L	= (P-L)/P	= 1-L/P	P-L OXPHOS-flux control efficiency
R-L control efficiency	j_R-L	= (R-L)/R	= 1-L/R	R-L ROUTINE-flux control efficiency
E-L coupling efficiency	j_E-L	= (E-L)/E	= 1-L/E	E-L ET-coupling efficiency » Biochemical coupling efficiency
E-P control efficiency	j_E-P	= (E-P)/E	= 1-P/E	E-P ET-excess flux control efficiency
E-R control efficiency	j_E-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

@@ Line 1: / Line 1: @@
 {{MitoPedia
-|abbr=''≈P''
+|abbr=''P-L''
-|description=[[Image:P-L.jpg|50 px|Free OXPHOS capacity]] The '''free OXPHOS capacity''', ''≈P'', is the [[OXPHOS capacity]] corrected for [[LEAK respiration]], ''≈P'' = ''P-L''. ''≈P'' is the scope for ADP stimulation, the respiratory capacity potentially available for phosphorylation of ADP to ATP. Oxygen consumption in the OXPHOS state, therefore, is partitioned into the free OXPHOS capacity, ''≈P'', strictly coupled to phosphorylation, ''~P'', and nonphosphorylating LEAK respiration, ''L<sub>P</sub>'', compensating for proton leaks, slip and cation cycling: ''P'' = ''≈P''+''L<sub>P</sub>''. It is frequently assumed that [[LEAK respiration]], ''L'', as measured in the LEAK state, overestimates the LEAK component of respiration, ''L<sub>P</sub>'', as measured in the OXPHOS state, particularly if the protonmotive force is not adjusted to equivalent levels in ''L'' and ''L<sub>P</sub>''. However, if the LEAK component increases with enzyme turnover during ''P'', the low enzyme turnover during ''L'' may counteract the effect of the higher Δ''p''<sub>mt</sub>.
+|description=[[Image:P-L.jpg|50 px|P-L net OXPHOS capacity|''P-L'' net OXPHOS capacity]] The '''''P-L'' net OXPHOS capacity''' is the [[OXPHOS capacity]] corrected for [[LEAK respiration]]. ''P-L'' is the scope for ADP stimulation, the respiratory capacity potentially available for phosphorylation of ADP to ATP. Oxygen consumption in the OXPHOS state, therefore, is partitioned into ''P-L'', strictly coupled to phosphorylation ''P»'', and nonphosphorylating LEAK respiration, ''L<sub>P</sub>'', compensating for proton leaks, slip and cation cycling: ''P'' = ''P-L''+''L<sub>P</sub>''. It is frequently assumed that [[LEAK respiration]] ''L'' as measured in the LEAK state, overestimates the LEAK component of respiration, ''L<sub>P</sub>'', as measured in the OXPHOS state, particularly if the protonmotive force is not adjusted to equivalent levels in ''L'' and ''L<sub>P</sub>''. However, if the LEAK component increases with enzyme turnover during ''P'', the low enzyme turnover during ''L'' may counteract the effect of the higher ''pmF''.
-|info=[[Gnaiger 2020 MitoPathways]]
+|info=[[Gnaiger 2020 BEC MitoPathways]]
 }}
-{{MitoPedia concepts
+ Communicated by [[Gnaiger E]] (2014-08-09) last update 2020-11-11
-|mitopedia concept=Respiratory state, Recommended
-}}
-{{MitoPedia methods}}
-{{MitoPedia O2k and high-resolution respirometry}}
-{{MitoPedia topics
-|mitopedia topic=EAGLE
-}}
-Communicated by [[Gnaiger E]] 2014-08-09, edited 2015-01-19.
-[[File:EPL-free and excess.jpg|right|240px|thumb|[[Gnaiger 2014 MitoPathways |The Blue Book 2014]]: Fig. 2.4.]]
-== Coupling control states for ''≈P'' ==
-::» [[Respiratory state]]
-* [[Reference state]], ''Z<sub>X</sub>'': [[Image:P.jpg|link=OXPHOS capacity|OXPHOS capacity]] [[OXPHOS capacity]], ''P'' = ''P´''-ROX
-* [[Background state]], ''Y<sub>X</sub>'': [[Image:L.jpg|link=LEAK respiration|LEAK]] [[LEAK respiration]], ''L'' = ''L´''-ROX
-* [[Metabolic control variable]], ''X=Z<sub>X</sub>-Y<sub>X</sub>'': [[Image:P-L.jpg|50 px|link=Free OXPHOS capacity |Free OXPHOS capacity]] Scope of ADP stimulation, [[free OXPHOS capacity]], ''≈P'' = ''P-L''
-== Flux control factor ==
-::» [[Flux control factor]], ''FCF''
-* [[Coupling control factor]], 1-''Y<sub>X</sub>/Z<sub>X</sub>'': [[Image:j--P.jpg|50 px|link=OXPHOS-coupling efficiency |OXPHOS-coupling efficiency]] ''P-L'' coupling control factor, [[OXPHOS-coupling efficiency]]: ''j<sub>≈P</sub>'' = ''≈P/P'' =(''P-L'')/''P'' = 1-''L/P''
-== Compare ==
+== Keywords ==
-:: [[Image:E-L.jpg|50 px|link=Free ET capacity |Free ET capacity]] [[Free ET capacity]], ''≈E'' = ''E-L''
+::::* Expand Bioblast links to '''''P-L'' net OXPHOS capacity'''
-:: [[Image:NetP over E.jpg|60 px|link=NetOXPHOS control ratio |netOXPHOS control ratio]] [[netOXPHOS control ratio]], ''≈P/E'' control ratio: ''≈P/E'' = (''P-L'')/''E''
+{{Template:Keywords: Coupling control}}
-:: [[Image:j--E.jpg|50 px|link=ET-coupling efficiency |ET-coupling efficiency]] [[ET-coupling efficiency]], ''E-L'' control factor: ''j<sub>≈E</sub>'' = ''≈E/E'' = (''E-L'')/''E'' = 1-''L/E''
-* Intact cells: [[Image:R-L.jpg|50 px|link=Free ROUTINE activity |Free ROUTINE activity]] [[Free ROUTINE activity]], ''≈R'' = ''R-L''