Abstract：
: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.
journal_name
Biochemistryjournal_title
Biochemistryauthors
Mirza IA,Nazi I,Korczynska M,Wright GD,Berghuis AMdoi
10.1021/bi051951ysubject
Has Abstractpub_date
2005-12-06 00:00:00pages
15768-73issue
48eissn
0006-2960issn
1520-4995journal_volume
44pub_type
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