coenzyme a

from the GNU version of the Collaborative International Dictionary of English.

• (Biochem.) a coenzyme (C21H36N7O16P3S) that participates in the transfer of acetyl groups in biochemical reactions; -- abbreviated CoA. It contains adenosine, phosphate, pantothenic acid and cysteamine groups. The acetyl group to be transferred during biosynthesis is temporarily attached to the free sulhydryl of the cysteamine group to form a thioester, in which state it is called acetyl coenzyme A. The strength of a preparation of coenzyme A may be expressed by the Lippman unit; one milligram of CoA contains 413 Lippman units.

from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.

• noun a coenzyme present in all living cells; essential to metabolism of carbohydrates and fats and some amino acids