Histone deacetylases "play crucial roles in gene transcription and most likely in all eukaryotic biological processes that involve chromatin".<ref name= Erasers/>
Two general mechanisms are known for deacetylation. One mechanism involves zinc binding to the acetyl oxygen. Another family of deacetylases require NAD+, which transfers an ribosyl group to the acetyl oxygen.<ref name= Erasers>Template:Cite journal</ref>
Many acetylations are achieved using these three reagents:
Acetic anhydride. This reagent is common in the laboratory; its use cogenerates acetic acid.<ref name=acetylfluorene /><ref name=":0">Template:Cite journal</ref>
Acetyl chloride. This reagent is also common in the laboratory, but its use cogenerates hydrogen chloride, which can be undesirable.<ref name=AcAnth />
Ketene. At one time acetic anhydride was prepared by the reaction of ketene with acetic acid:<ref name="Arpe">Template:Citation</ref>
Template:Chem2 <math>\Delta H = -63 \text{ kJ/mol}</math>
Acetylation of cellulose
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Cellulose is a polyol and thus susceptible to acetylation, which is achieved using acetic anhydride. Acetylation disrupts hydrogen bonding, which otherwise dominates the properties of cellulose. Consequently, the cellulose esters are soluble in organic solvents and can be cast into fibers and films.<ref>Template:Ullmann</ref>
The process involves the chemical reaction of acetic anhydride with the free hydroxyl groups in wood polymers, mostly of lignin and hemicelluloses, without requiring a catalyst. The modification results in bonds between the structural polymeric components, significantly reducing the ability of the -OH groups to form hydrogen bonds with water molecules. This effectively "locks" the cellular walls, minimizing the capacity of wood to absorb water and enhancing its dimensional stability. Approximately 80-90% of the hydroxyl groups of wood are modified during the process. The whole process is an environmentally friendly treatment, and has emerged, in the 21st century, as a significant innovation in the scientific area of wood science.<ref name=":0" /><ref>Template:Cite journal</ref>
Transacetylation
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Transacetylation uses vinyl acetate as an acetyl donor and lipase as a catalyst. This methodology allows the preparation of enantio-enriched alcohols and acetates.<ref>Template:Cite book</ref>
