19 pyruvate dehydrogenase

These flashcards cover key vocabulary and concepts related to the pyruvate dehydrogenase complex and its role in metabolism.

Pyruvate dehydrogenase

An enzyme complex that converts pyruvate into acetyl-CoA through oxidative decarboxylation.

Acetyl-CoA

A key substrate that links glycolysis to the citric acid cycle.

Mitochondria

Organelles responsible for aerobic respiration, which generate ATP.

Cofactor

A non-protein chemical compound that is necessary for the biological activity of a protein.

Thiamine pyrophosphate (TPP)

A cofactor for E1 that participates in the decarboxylation of pyruvate.

Dihydrolipoamide transacetylase

E2 enzyme in the PDH complex that transfers the acetyl group to CoA.

Oxidative decarboxylation

The process of losing carbon dioxide and oxidizing a substrate, which occurs in the PDH complex.

Electron transport chain

A series of complexes that transfer electrons from NADH and FADH2 to oxygen in aerobic respiration.

Substrate channeling

The efficient transfer of intermediates between enzymes in a metabolic pathway.

Coenzyme A (CoA)

A cofactor that assists in the transfer of acetyl groups during metabolic reactions.

Acetyl-dihydrolipoamide

The reaction product of transferring the 2C acetyl group from pyruvate to the lipoamide cofactor.

NAD+

A coenzyme that acts as an electron carrier in various metabolic pathways.

Oxidative phosphorylation

The metabolic pathway through which cells use enzymes to oxidize nutrients, thereby releasing energy which is used to reform ATP.

Hydroxyethyl-TPP

An intermediate formed during the decarboxylation of pyruvate by E1.

Lipoic acid

A cofactor that participates in the transfer of acyl groups in metabolic processes.

Dihydrolipoamide

The reduced form of lipoamide, which accepts electrons during the PDH complex reactions.

High-energy thioester bond

A type of bond in acetyl-CoA that stores energy for subsequent metabolic reactions.

E1

The first enzyme in the PDH complex, which decarboxylates pyruvate.

E2

The second enzyme in the PDH complex, responsible for transferring the acetyl group to CoA.

E3

The third enzyme in the PDH complex that re-oxidizes dihydrolipoamide and facilitates electron transfer.

Phosphorylation regulation

A process by which the activity of enzymes can be modified by the addition of phosphate groups.

Allosteric regulation

The regulation of an enzyme by binding an effector molecule at a site other than the enzyme's active site.

Lysine residue

An amino acid that can form covalent bonds with lipoic acid in the PDH complex.

Dynamic organelles

Mitochondria can form and change their networks in response to cellular needs.

Citric acid cycle

A series of chemical reactions used by all aerobic organisms to generate ATP.

Regeneration of NAD+

The process by which NADH is converted back to NAD+ allowing glycolysis to continue.

Decarboxylation of pyruvate

The removal of a carbon atom from pyruvate, producing carbon dioxide.