|PROSITE documentation PDOC00151 [for PROSITE entry PS00167]|
Tryptophan synthase (EC 18.104.22.168) catalyzes the last step in the biosynthesis of tryptophan: the conversion of indoleglycerol phosphate and serine, to tryptophan and glyceraldehyde 3-phosphate [1,2]. It has two functional domains: one for the aldol cleavage of indoleglycerol phosphate to indole and glyceraldehyde 3-phosphate and the other for the synthesis of tryptophan from indole and serine. In bacteria and plants , each domain is found on a separate subunit (α and β chains), while in fungi the two domains are fused together on a single multifunctional protein.
As a signature pattern for the α chain, we selected a conserved region that contains three conserved acidic residues. The first and the third acidic residues are believed to serve as proton donors/acceptors in the enzyme's catalytic mechanism.Last update:
November 2011 / Pattern revised.
PROSITE method (with tools and information) covered by this documentation:
|Title||Evolution of a biosynthetic pathway: the tryptophan paradigm.|
|Source||Annu. Rev. Microbiol. 43:567-600(1989).|
|2||Authors||Hyde C.C. Miles E.W.|
|Title||The tryptophan synthase multienzyme complex: exploring structure-function relationships with X-ray crystallography and mutagenesis.|
|Source||Biotechnology (N.Y.) 8:27-32(1990).|
|3||Authors||Berlyn M.B. Last R.L. Fink G.R.|
|Title||A gene encoding the tryptophan synthase beta subunit of Arabidopsis thaliana.|
|Source||Proc. Natl. Acad. Sci. U.S.A. 86:4604-4608(1989).|