MitoPedia: Terms and abbreviations

high-resolution terminology - matching measurements at high-resolution

MitoPedia: Terms and abbreviations

The MitoPedia terminology is developed continuously in the spirit of Gentle Science.

SI, IUPAC and MitoEAGLE recommendations

'The International System of Units, the SI, has been used around the world as the preferred system of units, the basic language for science, technology, industry and trade since it was established in 1960'. IUPAC guidelines are followed for general terms of physical chemistry^,,, extended by concepts of mitochondrial physiology and nonequilibrium thermodynamics,,.

According to BEC guidelines, 'manuscripts must adhere to SI units and IUPAC recommendations. MitoEAGLE recommendations on terms and symbols are to be implemented'.

Harmonization

Harmonization of some terms in mitochondrial physiology links separate 'subcultures' in publication. Ambiguities are pointed out for clarification of concepts. A platform-independent terminology is preferred. See also Table 2. Harmonization of terminology on respiratory states.

Table 1. Some platform-independent and platform-specific or outdated terms in mitochondrial physiology

Symbol	Platform-independent terms	Platform-specific or outdated terms
ce	living cells	intact cells
R	ROUTINE respiration, in ROUTINE state	basal respiration, in basal state
P	OXPHOS capacity, in OXPHOS state of mt-preparations	State 3
L	LEAK respiration	proton leak; State 4
E	ET capacity, electron transfer capacity	maximum respiration; State 3u
L/E	L/E coupling-control ratio	1/UCR = L/E (ambiguous)
L/P	L/P coupling-control ratio	1/RCR = L/P
R/E	R/E control ratio	1/UCR = E/R
R-L	R-L net ROUTINE capacity, net ROUTINE respiration	ATP production, ATP-linked respiration
E-R	E-R reserve capacity	spare capacity
Rox	residual oxygen consumption, in ROX state	nonmitochondrial respiration; State 2

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	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

• 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	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

» Flux control efficiency j_Z-Y

» Background state

» Reference state

» Metabolic control variable

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

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

Specific

» Artefacts by single dose uncoupling

» ATP synthase

» CCCP

» Coupling-control protocol

» DNP

» Dyscoupled respiration

» FCCP

» Is respiration uncoupled - noncoupled - dyscoupled?

» Noncoupled respiration: Discussion

» Uncoupler

» Uncoupled respiration - see » Noncoupled respiration

» Uncoupling proteins

» Uncoupling protein 1

» Uncoupler titrations - Optimum uncoupler concentration

Respiratory states and control ratios

» Biochemical coupling efficiency

» Coupling-control state

» Electron-transfer-pathway state

» Electron-transfer pathway

ET capacity

» E-L coupling efficiency

» Flux control efficiency

» Flux control ratio

» LEAK-control ratio

» LEAK respiration

» Noncoupled respiration

» OXPHOS

» OXPHOS capacity; » State 3

» OXPHOS-control ratio, P/E ratio

» Respiratory acceptor control ratio

» ROUTINE-control ratio

» ROUTINE respiration

» ROUTINE state

» State 3u

» State 4

» Uncoupling-control ratio UCR

• Gnaiger E et al ― MitoEAGLE Task Group (2020) Mitochondrial physiology. Bioenerg Commun 2020.1. https://doi.org/10.26124/bec:2020-0001.v1
• Gnaiger E (2020) Mitochondrial pathways and respiratory control. An introduction to OXPHOS analysis. 5th ed. Bioenerg Commun 2020.2. https://doi.org/10.26124/bec:2020-0002

General (alphabetical order)

» Adenine nucleotide translocase

» Adenylates

» Electron transfer pathway

» Mitochondrial preparations

» mt-membrane potential

» Oxygen flux

» Phosphorylation system

» Proton leak

» Proton slip

» TIP2k

Other keyword lists

» Template:Keywords: Force and membrane potential

Coupling control tables - >>>>>>> - Click on [Expand] or [Collapse] - >>>>>>>

• 

  The Blue Book 2020
  

• 

  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.