Acetyl-CoA, in addition to providing 2-carbon groups to the citric acid cycle, is also the substrate of enzymes that add acetyl groups to proteins. Histone acetyltransferase adds an acetyl group to the ε-amino group of a Lys residue in histones, proteins that interact closely with DNA. Draw the structure of the acetylated Lys side chain and explain why acetylation would disrupt the interaction between the histone and the DNA.