3. Deacetylation
Enzymatic or non-enzymatic lysine acetylation can be reversed by the action of lysine deacetylase (KDAC), also known as histone deacetylases (HDAC), since histones were the first identified substrate of the enzymes (Inoue & Fujimoto, 1969). Based on pairwise sequence comparisons and cofactor requirement, HDACs are grouped into four classes: the metal-dependent class I, II, and IV HDACs that do not require cofactors to deacetylated; and class III HDACs, commonly referred to as sirtuins, that are evolutionarily and mechanistically distinct family of NAD-dependent enzymes (Gregorett et al., 2004; Hentchel & Escalante-Semerena, 2015; Lombardi et al., 2011).