from
The Collaborative International Dictionary of English v.0.48
coenzyme A \co*en"zyme A`\ (k[-o]*[e^]n"z[imac]m [=a]`),
(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.
[PJC]