Description
Key facts
Sample types:Cell culture extracts, Tissue,
Reacts with:Mouse, Rat, Cow, Human, Pig,
Assay type:Sandwich (quantitative),
Assay Platform:Reagents
Product details:
ab109882 is used to quantify the activity of the PDH enzyme complex from human, bovine, mouse, rat and pig samples. This is accomplished by immunocapturing PDH with an anti-PDH antibody immobilized on a defined section of a dipstick. The enzyme complex is immunocaptured in its native form and activity is measured by the reaction scheme. PDH activity is visualized by coupling PDH-dependent production of NADH to the reduction of NBT in the presence of excess diaphorase, forming an insoluble intensely colored precipitate at the capture line. The signal intensity is measured by a dipstick reader or analyzed by other imaging systems such as a flatbed scanner.
Purified mitochondria can be used in this assay. However, homogenized tissue and whole cells can also be used without the need for mitochondrial isolation.
Pyruvate dehydrogenase activity is regulated by PDH kinase and PDH phosphatase. Cells grown in glucose media derive most of their energy from glycolysis; therefore, most of their PDH complex may be in an inactive phosphorylated form at the time of isolation. Growing cells in alternate carbon sources such as glutamine/galactose may up-regulate PDH activity. This kit does not include PDH kinases, PDH phosphatases or their respective inhibitors. These may be incorporated into the assay at the user's discretion.
Store dipsticks at room temperature out of direct sunlight in their provided desiccant container. Avoid high humidity conditions.
Store 20X Reagent Mix, Detergent, and Diaphorase at -80°C, but these may be aliquoted upon receipt to prevent freeze/thaw cycles.
Store NBT in the dark at -80°C.
Properties and Storage Information:
Shipped at conditions-Dry Ice, Appropriate short-term storage conditions-Multi, Appropriate long-term storage conditions-Multi, Storage information-Please refer to protocols
Supplementary Information:
This supplementary information is collated from multiple sources and compiled automatically.
Pyruvate dehydrogenase (PDH) is an enzyme complex also known as the pyruvate dehydrogenase complex (PDC) or PDH complex. It is a multi-enzyme structure with a mass on the order of megadaltons and plays an important role in cellular energy metabolism. Situated in the mitochondrial matrix pyruvate dehydrogenase converts pyruvate into acetyl-CoA through oxidative decarboxylation. This conversion releases one molecule of CO₂ and reduces NAD+ to NADH. The complex includes three core enzymes: E1 (pyruvate dehydrogenase) E2 (dihydrolipoamide acetyltransferase) and E3 (dihydrolipoamide dehydrogenase).
Biological function summary
The actions of pyruvate dehydrogenase serve as a bridge between glycolysis and the tricarboxylic acid (TCA) cycle. Pyruvate derived from glucose is transformed into acetyl-CoA before entering the TCA cycle for further energy extraction. The PDH complex ensures efficient energy production by tightly regulating the flow of carbon into the TCA cycle. Regulation occurs through phosphorylation by specific PDH kinases which inactivate E1. This mechanism integrates signals from energy status and substrates availability modulating the carbohydrate metabolism.
Pathways
Pyruvate dehydrogenase is a central player in cellular respiration and energy metabolism. It connects glycolytic pathways with the TCA cycle facilitating energy conversion in eukaryotic cells. Key related proteins involve pyruvate kinase (which generates pyruvate) and citrate synthase (which uses acetyl-CoA) ensuring synchronized activity between upstream and downstream metabolic processes. The proper function of PDH activity is necessary for maintaining the metabolic flow with the PDH complex serving a gating role in the energy pathways.
Pyruvate dehydrogenase deficiency results in metabolic challenges as the inability to convert pyruvate efficiently causes an increase in lactate levels. This condition results in lactic acidosis and severe neurological dysfunction. Furthermore alterations in PDH activity are observed in various forms of cancer as cancer cells often rely on aerobic glycolysis (Warburg effect) rather than complete oxidation of glucose. In this context the PDH protein interacts with oncogenic pathways highlighting its role in tumor metabolism and potential therapeutic targeting.
