| Primary Identifier | IPR000182 | Type | Domain |
| Short Name | GNAT_dom |
| description | The N-acetyltransferases (NAT) ([intenz:2.3.1.-]) are enzymes that use acetyl coenzyme A (CoA) to transfer an acetyl group to a substrate, a reaction implicated in various functions from bacterial antibiotic resistance to mammalian circadian rhythm and chromatin remodelling. The Gcn5-related N-acetyltransferases (GNAT) catalyse the transfer of the acetyl from the CoA donor to a primary amine of the acceptor. The GNAT proteins share a domain composed of four conserved sequence motifs A-D [, ]. This GNAT domain is named after yeast GCN5 (from General Control Nonrepressed) and related histone acetyltransferases (HATs) like Hat1 and PCAF. HATs acetylate lysine residues of N-terminal histone tails, resulting in transcription activation. Another category of GNAT, the aminoglycoside N-acetyltransferases, confer antibiotic resistance by catalysing the acetylation of amino groups in aminoglycoside antibiotics []. GNAT proteins can also have anabolic and catabolic functions in both prokaryotes and eukaryotes [, , , , ].The acetyltransferase/GNAT domain forms a structurally conserved fold of 6 to 7 β-strands (B) and 4 helices (H) in the topology B1-H1-H2-B2-B3-B4-H3-B5-H4-B6, followed by a C-terminal strand which may be from the same monomer or contributed by another [, ]. Motifs D (B2-B3), A (B4-H3) and B (B5-H4) are collectively called the HAT core [, , ], while the N-terminal motif C (B1-H1) is less conserved.Some proteins known to contain a GNAT domain:Actinobacterial mycothiol acetyltransferase (MshD), which catalyses the transfer of acetyl from acetyl-CoA to desacetylmycothiol to form mycothiol. Yeast GCN5 and Hat1, which are histone acetyltransferases (EC 2.3.1.48).Human PCAF, a histone acetyltransferase.Mammalian serotonin N-acetyltransferase (SNAT) or arylalkylamine NAT(AANAT), which acetylates serotonin into a circadian neurohormone that mayparticipate in light-dark rhythms, and human mood and behaviour.Mammalian glucosamine 6-phosphate N-acetyltransferase (GNA1) (EC 2.3.1.4).Escherichia coli RimI and RimJ, which acetylate the N-terminal alanine ofribosomal proteins S18 and S5, respectively (EC 2.3.1.128).Mycobacterium tuberculosis aminoglycoside 2'-N-acetyltransferase (Aac),which acetylates the 2' hydroxyl or amino group of a broad spectrum ofaminoglycoside antibiotics.Bacillus subtilis BltD and PaiA, which acetylate spermine and spermidine.This entry represents the entire GNAT domain. |
