CATH Classification

CATH Clusters

Superfamily Aldolase class I
Functional Family Tryptophan synthase alpha chain

Enzyme Information

4.2.1.20
Tryptophan synthase.
based on mapping to UniProt P00929
L-serine + 1-C-(indol-3-yl)glycerol 3-phosphate = L-tryptophan + D-glyceraldehyde 3-phosphate + H(2)O.
-!- The alpha-subunit catalyzes the conversion of 1-C-(indol-3- yl)glycerol 3-phosphate to indole and D-glyceraldehyde 3-phosphate (this reaction was listed formerly as EC 4.1.2.8). -!- The indole migrates to the beta-subunit where, in the presence of pyridoxal 5'-phosphate, it is combined with L-serine to form L-tryptophan. -!- In some organisms this enzyme is part of a multifunctional protein that also includes one or more of the enzymes EC 2.4.2.18, EC 4.1.1.48, EC 4.1.3.27 and EC 5.3.1.24. -!- In thermophilic organisms, where the high temperature enhances diffusion and causes the loss of indole, a protein similar to the beta subunit can be found (EC 4.2.1.122). -!- That enzyme cannot combine with the alpha unit of EC 4.2.1.20 to form a complex.

UniProtKB Entries (1)

P0A2K1
TRPB_SALTY
Salmonella enterica subsp. enterica serovar Typhimurium str. LT2
Tryptophan synthase beta chain

PDB Structure

PDB 1A5A
External Links
Method X-RAY DIFFRACTION
Organism Escherichia
Primary Citation
Cryo-crystallography of a true substrate, indole-3-glycerol phosphate, bound to a mutant (alphaD60N) tryptophan synthase alpha2beta2 complex reveals the correct orientation of active site alphaGlu49.
Rhee, S., Miles, E.W., Davies, D.R.
J.Biol.Chem.