Structural highlights
Function
METXA_HAEIN Transfers an acetyl group from acetyl-CoA to L-homoserine, forming acetyl-L-homoserine (PubMed:10913262, PubMed:28581482). Utilizes a ping-pong kinetic mechanism in which the acetyl group of acetyl-CoA is initially transferred to the enzyme to form an acetyl-enzyme intermediate before subsequent transfer to homoserine to form the final product, O-acetylhomoserine (PubMed:10913262).[1] [2]
Evolutionary Conservation
Check, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf.
Publication Abstract from PubMed
Homoserine transacetylase catalyzes one of the required steps in the biosynthesis of methionine in fungi and several bacteria. We have determined the crystal structure of homoserine transacetylase from Haemophilus influenzae to a resolution of 1.65 A. The structure identifies this enzyme to be a member of the alpha/beta-hydrolase structural superfamily. The active site of the enzyme is located near the end of a deep tunnel formed by the juxtaposition of two domains and incorporates a catalytic triad involving Ser143, His337, and Asp304. A structural basis is given for the observed double displacement kinetic mechanism of homoserine transacetylase. Furthermore, the properties of the tunnel provide a rationale for how homoserine transacetylase catalyzes a transferase reaction vs hydrolysis, despite extensive similarity in active site architecture to hydrolytic enzymes.
Crystal structure of homoserine transacetylase from Haemophilus influenzae reveals a new family of alpha/beta-hydrolases.,Mirza IA, Nazi I, Korczynska M, Wright GD, Berghuis AM Biochemistry. 2005 Dec 6;44(48):15768-73. PMID:16313180[3]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
References
- ↑ Born TL, Franklin M, Blanchard JS. Enzyme-catalyzed acylation of homoserine: mechanistic characterization of the Haemophilus influenzae met2-encoded homoserine transacetylase. Biochemistry. 2000 Jul 25;39(29):8556-64. PMID:10913262
- ↑ Bastard K, Perret A, Mariage A, Bessonnet T, Pinet-Turpault A, Petit JL, Darii E, Bazire P, Vergne-Vaxelaire C, Brewee C, Debard A, Pellouin V, Besnard-Gonnet M, Artiguenave F, Medigue C, Vallenet D, Danchin A, Zaparucha A, Weissenbach J, Salanoubat M, de Berardinis V. Parallel evolution of non-homologous isofunctional enzymes in methionine biosynthesis. Nat Chem Biol. 2017 Aug;13(8):858-866. doi: 10.1038/nchembio.2397. Epub 2017 Jun , 5. PMID:28581482 doi:http://dx.doi.org/10.1038/nchembio.2397
- ↑ Mirza IA, Nazi I, Korczynska M, Wright GD, Berghuis AM. Crystal structure of homoserine transacetylase from Haemophilus influenzae reveals a new family of alpha/beta-hydrolases. Biochemistry. 2005 Dec 6;44(48):15768-73. PMID:16313180 doi:http://dx.doi.org/10.1021/bi051951y
