Reactome: A Curated Pathway Database

Pyruvate + NADH + H+ <=> (S)-Lactate + NAD+ (R-HSA-71849)

Species Homo sapiens


Cytosolic lactate dehydrogenase catalyzes the reversible reaction of pyruvate and NADH + H+ to form lactate and NAD+. In the body under anaerobic conditions such as are found in red blood cells or rapidly exercising skeletal muscle, this reaction regenerates NAD+, allowing the continuation of glycolysis.

Lactate dehydrogenase is active as a tetramer. Two isoforms of lactate dehydrogenase, A and B, are widely expressed in human tissues, and all five tetramers - A4, A3B, A2B2, AB3, and B4 - are found. A third isoform, C, and its tetramer, C4, are found in testis.

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Additional Information
Compartment cytosol
Reverse Reaction (S)-Lactate + NAD+ <=> Pyruvate + NADH + H+
Components of this entry
Input entries
Output entries
Catalyst Activity
PhysicalEntity Activity Active Units
lactate dehydrogenase complex L-lactate dehydrogenase activity (0004459)