E-R control efficiency

high-resolution terminology - matching measurements at high-resolution

E-R control efficiency

Description

The apparent excess E-R capacity factor (E-R coupling control factor), j_ExR = (E-R)/E = 1-R/E, is an expression of the relative scope of increasing ROUTINE respiration in intact cells by uncoupling. j_ExR = 0.0 for zero excess capacity when R=E; j_ExR = 1.0 for the maximum limit when R=0. The ROUTINE state of intact cells is stimulated to ETS by uncoupler titration, which yields the excess E-R capacity, ExR=E-R. Since ETS capacity is significantly higher than OXPHOS capacity in various cell types (as shown by cell ergometry), ExR or j_ExR is not a reserve capacity available for the cell to increase oxidative phosphorylation, but strictly a scope (reserve?) for uncoupling respiration. Similarly, the apparent excess E-P capacity, ExP=E-P, is not a respiratory reserve in the sense of oxidative phosphorylation.

Abbreviation: j_ExR

Reference: Flux control factor

MitoPedia concepts: Respiratory control ratio 

Compare

» ROUTINE control ratio, R/E

» Excess E-P capacity factor, j_ExP = (E-P)/E = 1-P/E

» ETS coupling efficiency, j_≈E = 1-L/E