Quantification of In Vitro Protein Lysine Acetylation by Reversed Phase HPLC

Protein lysine acetylation is a reversible posttranslational modification that is catalyzed by a group of enzymes that are collectively referred to as lysine (K) acetyltransferases (KATs). These enzymes catalyze the transfer of the acetyl group from acetyl coenzyme A (Ac-CoA) to the ε-amino group of lysine amino acid. Protein lysine acetylation plays a critical role in the regulation of important cellular processes and it is therefore paramount that we understand the catalytic mechanisms of these enzymes. While there is a variety of methods that have been developed to analyze the enzymatic properties of KATs, majority of the proposed methods have considerable limitations. We describe here a reversed phase HPLC based method that monitors substrate consumption and product formation simultaneously. This method is highly reproducible and optimally suited for the determination of accurate kinetic parameters of KATs.