Related Experiment Video
Updated: Aug 13, 2026

Inner Mitochondrial Membrane Sensitivity to Na+ Reveals Partially Segmented Functional CoQ Pools
Published on: July 20, 2022
Interaction of succinate Ubiquinone reductase with sulphate ion
Z M Chaudhry1, M A Khan, A D Vinogradov
1Department of Pharmacy, BZ University, Multan, Pakistan.
Abstract:
A new type of slow change of succinate Ubiquinone reductase (EC 1.3.99), activity which is induced by sulphate ion is described. After preincubation of submitochondrial particles or succinate ubiquinone reductase with sulphate both preparations catalyze succinate: phenazine methosulphate reductase reaction with a significant lag. When added to the assay medium sulphate ion induces biphasic time-dependent competitive inhibition of the enzyme. The sulphate-induced inhibition is apparently due to a rapid interaction of the anion with an active site of the enzyme which is followed by a slow pH-dependent (pK = 7.2) transformation of the enzyme inhibitor complex. pH profiles of the overall succinate ubiquinone reductase reaction and of equilibrium between fast and slow enzyme-sulphate complexes suggest that the same protolytic equilibrium step is involved in the formation of an active intermediate and an inactive enzyme-sulphate complex.
More Related Videos
08:03Unveiling Xenobiotic Transport and Effects in Isolated Mitochondria: Insights from Respirometric and Enzymatic Assays
Published on: March 7, 2025
14:39Cholinergic Ligand–dependent Modulation of Oxidative Phosphorylation Coupling in Digitonin-permeabilized BE(2)-C Neuroblastoma Cells
Published on: April 28, 2026
Related Concept Videos
Electron Transport Chain: Complex I and II
ROS generation is regulated and maintained at moderate levels necessary...
Electron Transport Chain: Complex III and IV
The Electron Transport Chain
Inhibitors of the electron transport chain
Rotenone, a widely used pesticide, prevents electron transfer from Fe-S cluster to ubiquinone or Q in...
Electron Transport Chains
The ETC is comprised of...
Sulfur Assimilation
The Citric Acid Cycle