Acetyltransferase

Acetyltransferase is an enzyme that catalyzes the transfer of an acetyl group from acetyl-CoA to a recipient substrate. Acetylation can target amino groups, hydroxyl groups, or other nucleophiles, yielding an acetylated product and CoA-SH. The general reactions are R-NH2 + Acetyl-CoA -> R-NH-CO-CH3 + CoA-SH or R-OH + Acetyl-CoA -> R-O-CO-CH3 + CoA-SH.

Classification and examples: The most common families are GNAT (GCN5-related N-acetyltransferases) and various histone acetyltransferases (HATs) such as the MYST and p300/CBP families. HATs modify histones and other proteins, influencing gene expression by changing chromatin structure. N-acetyltransferases in bacteria and archaea can acetylate small molecules, proteins, or drugs.

Biological roles: In eukaryotes, histone acetylation generally promotes transcription by reducing histone-DNA affinity; acetylation also regulates non-histone proteins. In prokaryotes, acetylation participates in metabolism and regulation; many bacterial acetyltransferases participate in inactivating antibiotics, contributing to resistance when they acetylate aminoglycoside antibiotics.

Clinical and biotechnological relevance: Dysregulation of acetyltransferases is linked to cancer and metabolic diseases; inhibitors of HATs are under investigation. In medicine and research, acetyltransferases can be therapeutic targets or used in the synthesis of acetylated compounds for various applications.