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any of a group of enzymes that catalyze the reversible transfer of an amino group from a donor, usually an amino acid, to an acceptor, usually a 2-keto acid. Most use pyridoxal phosphate as a coenzyme.
Enzyme that transfers amino groups from an amino acid to a keto acid, for example, l-alanine and 2-ketoglutarate. Often, the amino acid is an α-amino acid and the keto acid is an α-keto acid.
aminotransferase/ami·no·trans·fer·ase/ (-trans´fer-ās) transaminase.
aminotransferase(ə-mē′nō-trăns′fə-rās′, -rāz′, ăm′ə-)
enzymes that catalyze the transfer of an amino group from an amino acid to an alpha-keto acid, with pyridoxal phosphate and pyridoxamine phosphate acting as coenzymes. Aspartate aminotransferase (AST), normally present in serum and various tissues, especially in the heart and liver, is released by damaged cells, and as a result, a high serum level may be diagnostic of myocardial infarction or hepatic disease. Alanine aminotransferase, a normal constituent of serum, especially in the liver, is released by injured tissue and may be present in high concentrations in the sera of patients with acute liver disease. Previously called transaminase.
an enzyme that catalyzes the reversible transfer of an amino group from an α-amino acid to an α-keto acid using the coenzyme pyridoxal phosphate. Called also transaminase.
an enzyme that has high serum levels after acute damage to liver cells. Called also ALT. See also alanine aminotransferase.
an enzyme that has high serum levels after skeletal muscle damage or acute damage to liver cells. Called also AST. See also aspartate aminotransferase.