Deacetylating

Deacetylating or deacetylation is the removal of acetyl groups from molecules, most often from acetylated proteins such as histones, but also from small molecules and synthetic compounds. The acetyl group is a two-carbon acyl moiety attached by an ester or amide linkage to a substrate. Removal can occur enzymatically in biological systems or chemically in laboratory or industrial settings.

Biology: In chromatin, histone deacetylases (HDACs) remove acetyl groups from lysine residues on histone tails, promoting chromatin condensation and transcriptional repression. A related group, sirtuins, are NAD+-dependent deacetylases that target histones and many non-histone proteins, linking cellular metabolism to regulation of gene expression and protein activity. Deacetylation can modulate enzyme activity, protein stability, interaction networks, and subcellular localization. Abnormal deacetylation is associated with diseases and is a target for therapeutics, including cancer and neurodegenerative diseases.

Chemistry and pharmacology: Deacetylation is also a standard protecting-group strategy in organic synthesis (removing acetyl protections from amines or alcohols to reveal the free functional groups) typically achieved by hydrolysis with acids or bases or by specific reagents. In drug metabolism, acetylated drugs may be hydrolyzed to active or inactive forms; aspirin, for example, can be deacetylated to salicylic acid. Reactions can be chemical or enzymatic, and the conditions depend on the substrate and desired product.