Acetyltransferases

From Biomatics.org

Histone acetyltransferases (HAT) are enzymes that acetylate conserved lysine amino acids on histone proteins by transferring an acetyl group from acetyl CoA to form ε-N-acetyl lysine.

Histone acetylation is generally linked to transcriptional activation. These are generally associated with euchromatin. Initially, it was thought that acetylation of lysine neutralizes the positive charge normally present, thus reducing affinity between histone and (negatively charged) DNA which renders DNA more accessible to transcription factors. More recently, it has emerged that lysine acetylation and other posttranslational modifications of histones generate binding sites for specific protein-protein interaction domains, such as the acetyl-lysine binding bromodomain.^{[citation needed]}