Nicotinamide adenine dinucleotide

Definition

Nicotinamide adenine dinucleotide (NAD+) is a coenzyme found in all living cells. It plays a crucial role in redox reactions, carrying electrons from one reaction to another.

5 Must Know Facts For Your Next Test

1. NAD+ acts as an electron carrier in the metabolic pathways of glycolysis and the citric acid cycle.
2. In its reduced form, NADH, it donates electrons to the electron transport chain for ATP production.
3. NAD+ is derived from vitamin B3 (niacin).
4. The ratio of NAD+ to NADH within a cell is indicative of its metabolic state.
5. NAD+ also functions as a substrate for enzymes involved in post-translational modifications.

Review Questions

• What role does NAD+ play in redox reactions?
• How does the conversion between NAD+ and NADH impact cellular respiration?
• Why is the ratio of NAD+ to NADH important for cellular metabolism?

Related terms

ATP:

Adenosine triphosphate, the primary energy carrier in cells.

Glycolysis:

The process of breaking down glucose into pyruvate, producing ATP and NADH.

Electron Transport Chain:

A series of protein complexes that transfer electrons from electron donors to acceptors via redox reactions and produce ATP.