MiPNet12.01 Suppl T-issue
MitoPathways at the Q-junction. |
OROBOROS (2014-07) Mitochondr Physiol Network
Abstract:
OROBOROS (2014) MitoPathways at the Q-junction. Mitochondr Physiol Network 12.01(02): Supplementary T-issue.
High-resolution respirometry presented as supplementary T-issue (OROBOROS T-shirt). OXPHOS analysis in O2k-experiment 2007-04-14 A-03 (IOC39, April 2007, SchrΓΆcken, Vorarlberg, Austria). In permeabilized mouse skeletal muscle, addition of pyruvate+glutamate+malate (PGM) induced CI-linked LEAK respiration. Saturating ADP (D) stimulated respiration to the level of OXPHOS capacity (P state), with a small effect of 10 Β΅M cytochrome c (c), expressed as the cytochrome c control factor (FCFc<0.5; indicating integrity of the outer mt-membrane). Addition of succinate (S) stimulated respiration by convergent e-input through the Q-junction. CI+II OXPHOS capacity is not stimulated ETS capacity (E state) further by uncoupler titration (U). At E=P the E-P coupling control factor is zero, indicating that there is no ETS excess capacity over P. Inhibition of CI by rotenone (Rot) inhibited respiration to the level of CII-linked ETS capacity, which is higher than CI-linked respiratory capacity (E=P). CI+II-linked respiratory capacity was higher than respiration with any single e-input substrate state, indicating an additive effect at the Q-junction. However, since CI+II < CI+CII, the additive effect was incomplete, which indicates that any electron channelling through supercomplexes to CIV was incomplete. Addition of azide (Azd) inhibited respiration to the level of residual oxygen consumption (ROX). The fact that ROX was higher in the CI+II substrate state compared to CI-linked LEAK respiration indicates that ROX is partially controlled by the substrate state, and a single measurement of ROX can thus not be applied for correction of total oxygen consumption. Total respiration, therefore, represents apparent coupling states LΒ΄, PΒ΄ and EΒ΄. Evaluation of maximum respiratory capacities requires further titration of substrates activating additional respiratory complexes at the Q-junction (CETF and CGpDH).
- >> Product: OROBOROS Oxygraph-2k, O2k-Catalogue
β’ O2k-Network Lab: AT_Innsbruck_OROBOROS
Labels: MiParea: Respiration
Organism: Mouse
Tissue;cell: Skeletal muscle
Preparation: Permeabilized tissue
Coupling state: LEAK, ROUTINE, ETS"ETS" is not in the list (LEAK, ROUTINE, OXPHOS, ET) of allowed values for the "Coupling states" property.
HRR: Oxygraph-2k, Protocol"Protocol" is not in the list (Oxygraph-2k, TIP2k, O2k-Fluorometer, pH, NO, TPP, Ca, O2k-Spectrophotometer, O2k-Manual, O2k-Protocol, ...) of allowed values for the "Instrument and method" property.
MitoPathways, O2k-Demo, O2k-Core