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In biochemistry, transferase is the general name for the class of enzymes that enact the transfer of specific functional groups (e.g. a methyl or glycosyl group) from one molecule (called the donor) to another (called the acceptor). They are involved in hundreds of different biochemical pathways throughout biology, and are integral to some of life’s most important processes. Transferases are involved in myriad reactions in the cell. Some examples of these reactions include the activity of CoA transferase, which transfers thiol esters, the action of N-acetyltransferase is part of the pathway that metabolizes tryptophan, and also includes the regulation of PDH, which converts pyruvate to Acetyl CoA. Transferases are also utilized during translation. In this case, an amino acid chain is the functional group transferred by a Peptidyl transferase. The transfer involves the removal of the growing amino acid chain from the tRNA molecule in the A-site of the ribosome and its subsequent addition to the amino acid attached to the tRNA in the P-site.〔Watson, James D. Molecular Biology of the Gene. Upper Saddle River, NJ: Pearson, 2013. Print.〕 Mechanistically, an enzyme that catalyzed the following reaction would be a transferase: In the above reaction, X would be the donor, and Y would be the acceptor. "Group" would be the functional group transferred as a result of transferase activity. The donor is often a coenzyme. ==History== Some of the most important discoveries relating to transferases occurred as early as the 1930s. Earliest discoveries of transferase activity occurred in other classifications of enzymes, including Beta-galactosidase, protease, and acid/base phosphatase. Prior to the realization that individual enzymes were capable of such a task, it was believed that two or more enzymes enacted functional group transfers. Transamination, or the transfer of an amine (or NH2) group from an amino acid to a keto acid by an aminotransferase (also known as a "transaminase"), was first noted in 1930 by D. M. Needham, after observing the disappearance of glutamic acid added to pigeon breast muscle. This observance was later verified by the discovery of its reaction mechanism by Braunstein and Kritzmann in 1937. Their analysis showed that this reversible reaction could be applied to other tissues. This assertion was validated by Rudolf Schoenheimer's work with radioisotopes as tracers in 1937. This in turn would pave the way for the possibility that similar transfers were a primary means of producing most amino acids via amino transfer. Another such example of early transferase research and later reclassification involved the discovery of uridyl transferase. In 1953, the enzyme UDP-glucose pyrophosphorylase was shown to be a transferase, when it was found that it could reversibly produce UTP and G1P from UDP-glucose and an organic pyrophosphate. Another example of historical significance relating to transferase is the discovery of the mechanism of catecholamine breakdown by catechol-O-methyltransferase. This discovery was a large part of the reason for Julius Axelrod’s 1970 Nobel Prize in Physiology or Medicine (shared with Sir Bernard Katz and Ulf von Euler). Classification of transferases continues to this day, with new ones being discovered frequently. An example of this is Pipe, a sulfotransferase involved in the dorsal-ventral patterning of ''Drosophilia''. Initially, the exact mechanism of Pipe was unknown, due to a lack of information on its substrate. Research into Pipe's catalytic activity eliminated the likelihood of it being a heparan sulfate glycosaminoglycan. Further research has shown that Pipe targets the ovarian structures for sulfation. Pipe is currently classified as a ''Drosophilia'' heparan sulfate 2-O-sulfotransferase. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Transferase」の詳細全文を読む スポンサード リンク
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