A introdución dun grupo acetilo nunha molécula denomínase [[acetilación]]. Nos seres vivos os grupos acetilo transfírense xeramente unidos ao [[coencima A]], formando [[acetil-CoA]]. O acetil-CoA é un intermediario tanto na síntese biolóxica coma na degradación de moitas moléculas orgánicas. O acetil-CoA tamén se orixina durante a segunda parte da [[respiración celular]], o [[ciclo de Krebs]]. Fórmase a partir de [[piruvato]] e o grupo acetilo é cedido ao [[oxalacetato]] do ciclo de Krebs.
The introduction of an acetyl group into a molecule is called [[acetylation]]. In biological organisms, acetyl groups are commonly transferred from acetyl-CoA to [[coenzyme A]] (CoA). Acetyl-CoA is an intermediate both in the biological synthesis and in the breakdown of many organic molecules. Acetyl-CoA is also created during the second stage of cellular respiration, the Kreb's Cycle. It is formed from pyruvic acid with the help of water and is later bonded to a pre-existing four-carbon molecule to carry out the Kreb's Cycle.
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