CoA

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]

from The Collaborative International Dictionary of English v.0.48

CoA \CoA\ (k[-o]*[=a]"), (Biochem)
   an abbreviation for {coenzyme A}.
   [PJC]

from V.E.R.A. -- Virtual Entity of Relevant Acronyms (June 2006)

COA
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