Alanine dehydrogenase (EC 1.4.1.1) is an enzyme that catalyzes the chemical reaction

L-alanine + H₂O + NAD⁺ ${\displaystyle \rightleftharpoons }$ pyruvate + NH₃ + NADH + H⁺

The 2 substrates of this enzyme are L-alanine, water, and nicotinamide adenine dinucleotide⁺ because water is 55M and does not change, whereas its 4 products are pyruvate, ammonia, NADH, and hydrogen ion.

This enzyme participates in taurine and hypotaurine metabolism and reductive carboxylate cycle (CO₂ fixation).

This enzyme belongs to the family of oxidoreductases, specifically those acting on the CH-NH₂ group of donors with NAD⁺ or NADP⁺ as acceptor. The systematic name of this enzyme class is L-alanine:NAD⁺ oxidoreductase (deaminating). Other names in common use include AlaDH, L-alanine dehydrogenase, NAD⁺-linked alanine dehydrogenase, alpha-alanine dehydrogenase, NAD⁺-dependent alanine dehydrogenase, alanine oxidoreductase, and NADH-dependent alanine dehydrogenase. T

Alanine dehydrogenase contains both a N-terminus^[1] and C-terminus domains.^[2][3]