Transferase(redirected from glutathione S-t's)
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any of a class of enzymes that catalyze the transfer of a chemical group from one compound (the donor) to another (the acceptor). Transferases are common in plant and animal tissues, as well as in microorganisms. They play a leading role in intermediary metabolism, participating in the transformations of carbohydrates, amino acids, nucleic acids, lipids, and other biologically important compounds.
The transferase class includes more than 450 enzymes, divided by the chemical nature of the group being transferred into subclasses. Examples include the subclasses that catalyze the transfer of single-carbon groups (methyltransferases), glycosyl groups (glycosyltransferases), nitrogen-bearing groups (aminotransferases, or transaminases), and phosphate groups (phosphotransferases). The transferases of the various subclasses have different coenzymes.
The mechanism of the catalytic action of the transferases studied to date includes the formation of an intermediate made up of the enzyme and group being transferred. For example, in the transfer of the acetyl radical (CH3CO—), an acetylated enzyme is formed in the first stage of the reaction, followed by the transfer of the radical to the acceptor and the liberation of the enzyme. The names of transferases are formed according to the sequence dononacceptor-transferred group-transferase. For example, the enzyme that catalyzes the transfer of the phosphate group from adenosinetriphosphate (ATP) to creatine is called ATP:creatine-phosphotransferase. Several transferases have been obtained in crystalline form.
REFERENCESNomenklatura fermentov. Moscow, 1966. (Translated from English.)
Kretovich, V. L. Vvedenie v enzimologiiu, 2nd ed. Moscow, 1974.
V. V. ZUEVSKII