Transaminases are a sub-subclass of mostly pyridoxal phosphate-dependent transferase enzymes that catalyze the transfer of an amino group from a donor (generally an amino acid) to an acceptor (generally a 2-keto acid). Mediating conversion of major intermediate metabolites and reversible transamination, Transaminases are often involved in cellular nitrogen metabolism, amino acid metabolism, gluconeogenesis and in the urea and tricarboxylic acid cycles.

A subclass of enzymes of the transferase class that catalyze the transfer of an amino group from a donor (generally an amino acid) to an acceptor (generally a 2-keto acid). Most of these enzymes are pyridoxyl phosphate proteins. (Dorland, 28th ed) EC 2.6.1.