21. This enzyme covalently attaches an acetyl group from acetyl-CoA to chloramphenicol, which prevents chloramphenicol from binding to ribosomes. 22. The deprotonated group is now free to attack the acetyl group of acetyl-CoA or acetylcarnitine at its carbonyl site. 23. Lastly, a post-NRPS modification happens in the free hydroxyl group from the second isovaleric acid, adding an acetyl group . 24. It differs from the acetyl group CH 3-C ( = O )-by the presence of one additional oxygen atom. 25. ChAT catalyzes the transfer of an acetyl group from the coenzyme, acetyl-CoA, to choline yielding acetylcholine ( ACh ). 26. After ethanol sedation of the flies occurs, acetyl groups are added to histones within the " slo " promoter region. 27. After the transfer of the acetyl group has occurred, the products are orderly released with N-acetyl-serotonin first and CoA last. 28. Many researchers had assumed that sir2 was likely to perform its gene-silencing role by stripping acetyl groups off the chromatin. 29. Acetylcholine is synthesized from choline and a donated acetyl group from acetyl-CoA, by the action of choline acetyltransferase ( ChAT ). 30. As a posttranslational modification, the acetylation of histones can attract proteins to elongated chromatin that has been marked by acetyl groups .
