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, promoting a nucleophilic attack from the deprotonated oxygen | 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 to the thioester bond of the acetyl-CoA. The intermediate produced, 3-acetylchloramphenicol, then rearranges non-enzymatically to 1-acetylchloramphenicol. Regeneration of the 3-hydroxyl allows another CAT III catalyzed nucleophilic attack to another acetyl-CoA and a 1,3-diacetylchloramphenicol product is formed. | ||
Revision as of 04:27, 21 March 2010
Anthony Daniele
Chloramphenicol Acetyltransferase Type III
Chloramphenicol acetyltransferase type III (CAT III) is an enzyme which catalyzes the transfer of acetyl from acetyl-CoA to hydroxyl groups of chloramphenicol. CAT III is a trimeric protein
Introduction
Reaction of CAT III
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 to the thioester bond of the acetyl-CoA. The intermediate produced, 3-acetylchloramphenicol, then rearranges non-enzymatically to 1-acetylchloramphenicol. Regeneration of the 3-hydroxyl allows another CAT III catalyzed nucleophilic attack to another acetyl-CoA and a 1,3-diacetylchloramphenicol product is formed.
| Please do NOT make changes to this Sandbox until after April 23, 2010. Sandboxes 151-200 are reserved until then for use by the Chemistry 307 class at UNBC taught by Prof. Andrea Gorrell. |
