Profile: Immunechem Pharmaceuticals Inc. offers assay kits and modification state antibodies. Affinity purified polyclonal anti-acetylated lysine antibody is developed using acetylated KLH as immunogen. The purified antibody was conjugated to horseradish peroxidase (HRP) through reductive amination. Acetylation of lysine is an important reversible modification process. The activity of some proteins is controlled by this process. Histone acetyltransferases acetylate the conserved amino-terminal domains of the four core histones (H2A, H2B, H3 and H4) that contain lysine residues. Histone H4 antibody is subjected to purification process with histone H4 peptide. Histones are the main proteins of chromatin. Histones are also involved in gene regulation. Histone H4 consists of a main globular domain, and a long N-terminal tail.