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A cofactor is a non-protein chemical molecule or metallic ion required for an enzyme's catalytic function (a catalyst is a substance that increases the rate of a chemical reaction).

Cofactors are required in the citric acid cycle

• CoASH - Coenzyme A (CoA, CoASH, or HSCoA) is a coenzyme that plays a key part in the synthesis and oxidation of fatty acids, as well as the citric acid cycle's pyruvate oxidation.
• NAD⁺ (Nicotinamide adenine dinucleotide) - Citrate conducts an oxidation reaction after undergoing a rearrangement step, sending electrons to NAD+ to produce NADH and releasing a molecule of carbon dioxide.
• Lipoamide - Two enzymes in the citric acid cycle require the cofactor lipoamide. It's also required for the production of nucleic acids and the metabolism of branched-chain amino acids.
• TPP (Thiamine pyrophosphate) - Thiamine pyrophosphate (TPP) is a crucial cofactor for key processes in the Krebs cycle, such as pyruvate decarboxylation and alpha-ketoglutamic acid oxidation; as a result, thiamine serves as a vital connection between the glycolytic and citric acid cycles.
• FAD (Flavin Adenine Dinucleotide – Flavin adenine dinucleotide is used in this oxidation-reduction process (FAD).

A prosthetic group is a non-amino acid component that is closely connected to the apoprotein and is part of the structure of hetero proteins or conjugated proteins.

The prosthetic groups are

• TPP (Thiamine pyrophosphate)
• FAD (Flavin Adenine Dinucleotide)
• NAD⁺ (Nicotinamide Adenine Dinucleotide)