Sandbox 156: Difference between revisions

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In the first step of the reaction, Histidine-156 abstracts a proton from the 3-hydroxyl of chloramphenicol, causing a nucleophilic attack from the deprotonated oxygen onto the thioester bond of the acetyl-CoA. The 3-acetylchloramphenicol intermediate then rearranges, non-enzymatically, to a 1-acetylchloramphenicol intermediate. CAT III then causes another acetylation of the now regenerated 3-hydroxyl and 1,3-diacetylchloramphenicol is produced.
In the first step of the reaction, Histidine-156 abstracts a proton from the 3-hydroxyl of chloramphenicol, promoting a nucleophilic attack from the deprotonated oxygen onto the thioester bond of the acetyl-CoA. The 3-acetylchloramphenicol intermediate then rearranges, non-enzymatically, to a 1-acetylchloramphenicol intermediate. CAT III then causes another acetylation of the now regenerated 3-hydroxyl and 1,3-diacetylchloramphenicol is produced.