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ENZYME entry: EC

Accepted Name
tryptophan synthase (indole-salvaging)
Alternative Name(s)
tryptophan synthase beta2
Reaction catalysed
indole + L-serine <=> H2O + L-tryptophan
  • Most mesophilic bacteria have a multimeric tryptophan synthase complex (EC that forms L-tryptophan from L-serine and 1-C- (indol-3-yl)glycerol 3-phosphate via an indole intermediate.
  • This intermediate, which is formed by the alpha subunits, is transferred in an internal tunnel to the beta units, which convert it to tryptophan.
  • In thermophilic organisms the high temperature enhances diffusion and causes the loss of indole.
  • This enzyme, which does not combine with the alpha unit to form a complex, salvages the lost indole back to L-tryptophan.
  • It has a much lower Km for indole than the beta subunit of EC
PRIAM enzyme-specific profiles4.2.1.122
KEGG Ligand Database for Enzyme Nomenclature4.2.1.122
IUBMB Enzyme Nomenclature4.2.1.122
MEDLINEFind literature relating to
Rhea expert-curated reactions4.2.1.122

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