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MetaCyc Reaction:

Superclasses: Reactions Classified By Conversion TypeSimple ReactionsChemical ReactionsComposite Reactions
Reactions Classified By Conversion TypeSimple ReactionsChemical Reactions
Reactions Classified By SubstrateSmall-Molecule Reactions

EC Number:

Enzymes and Genes:

Escherichia coli K-12 substr. MG1655: tryptophan synthaseInferred from experiment: trpA, trpB
Thermococcus kodakarensis: tryptophan synthase complexInferred from experiment: trpA, trpB
Thermotoga maritima: tryptophan synthase: trpA, trpB1

The direction shown, i.e. which substrates are on the left and right sides, is in accordance with the Enzyme Commission system.

Mass balance status: Balanced.

Enzyme Commission Primary Name: tryptophan synthase

Enzyme Commission Synonyms: L-tryptophan synthetase, indoleglycerol phosphate aldolase, tryptophan desmolase, tryptophan synthetase, L-serine hydro-lyase (adding indoleglycerol-phosphate), L-serine hydro-lyase [adding 1-C-(indol-3-yl)glycerol 3-phosphate, L-tryptophan and glyceraldehyde-3-phosphate-forming]

Taxonomic Range: Fungi, Viridiplantae, Archaea, Bacteria

(1S,2R)-1-C-(indol-3-yl)glycerol 3-phosphate ↔ indole + D-glyceraldehyde 3-phosphate,
L-serine + indole → L-tryptophan + H2O

Standard Gibbs Free Energy (ΔrG in kcal/mol): 11.682007Inferred by computational analysis [Latendresse13]

Enzyme Commission Summary:
A pyridoxal-phosphate protein. The α-subunit catalyses the conversion of 1-C-(indol-3-yl)glycerol 3-phosphate to indole and glyceraldehyde 3-phosphate (this reaction was listed formerly as EC The indole migrates to the β-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 (anthranilate phosphoribosyltransferase), EC (indole-3-glycerol-phosphate synthase), EC (anthranilate synthase) and EC (phosphoribosylanthranilate isomerase). In thermophilic organisms, where the high temperature enhances diffusion and causes the loss of indole, a protein similar to the α subunit can be found ( EC That enzyme cannot combine with the β unit of EC to form a complex.

Citations: [Crawford58, Hutter86, Hyde88, Woehl99]

Gene-Reaction Schematic

Gene-Reaction Schematic

Unification Links: KEGG:R02722, Rhea:10532

Relationship Links: BRENDA:EC:, ENZYME:EC:, IUBMB-ExplorEnz:EC:, UniProt:RELATED-TO:O04225, UniProt:RELATED-TO:O05625, UniProt:RELATED-TO:O13831, UniProt:RELATED-TO:O22765, UniProt:RELATED-TO:O27696, UniProt:RELATED-TO:O28672, UniProt:RELATED-TO:O64991, UniProt:RELATED-TO:O66923, UniProt:RELATED-TO:O84172, UniProt:RELATED-TO:P00929, UniProt:RELATED-TO:P00931, UniProt:RELATED-TO:P06561, UniProt:RELATED-TO:P06562, UniProt:RELATED-TO:P07600, UniProt:RELATED-TO:P07601, UniProt:RELATED-TO:P0A2K1, UniProt:RELATED-TO:P0A877, UniProt:RELATED-TO:P0A879, UniProt:RELATED-TO:P11080, UniProt:RELATED-TO:P11081, UniProt:RELATED-TO:P12290, UniProt:RELATED-TO:P12291, UniProt:RELATED-TO:P13228, UniProt:RELATED-TO:P14671, UniProt:RELATED-TO:P16578, UniProt:RELATED-TO:P16608, UniProt:RELATED-TO:P16706, UniProt:RELATED-TO:P17166, UniProt:RELATED-TO:P17167, UniProt:RELATED-TO:P18284, UniProt:RELATED-TO:P18285, UniProt:RELATED-TO:P19867, UniProt:RELATED-TO:P19868, UniProt:RELATED-TO:P25269, UniProt:RELATED-TO:P31204, UniProt:RELATED-TO:P34793, UniProt:RELATED-TO:P34816, UniProt:RELATED-TO:P34817, UniProt:RELATED-TO:P42389, UniProt:RELATED-TO:P42390, UniProt:RELATED-TO:P42391, UniProt:RELATED-TO:P43283, UniProt:RELATED-TO:P43284, UniProt:RELATED-TO:P43759, UniProt:RELATED-TO:P43760, UniProt:RELATED-TO:P50909, UniProt:RELATED-TO:P51382, UniProt:RELATED-TO:P56142, UniProt:RELATED-TO:P77960, UniProt:RELATED-TO:Q9JVC0, UniProt:RELATED-TO:Q9PIF1, UniProt:RELATED-TO:Q9PIF2, UniProt:RELATED-TO:Q9X7C8, UniProt:RELATED-TO:Q9YGA9, UniProt:RELATED-TO:Q9YGB0, UniProt:RELATED-TO:Q01997, UniProt:RELATED-TO:Q01998, UniProt:RELATED-TO:Q42529, UniProt:RELATED-TO:Q57011, UniProt:RELATED-TO:Q59992, UniProt:RELATED-TO:Q60179

Revised 25-Aug-2011 by Caspi R, SRI International


Crawford58: Crawford IP, Yanofsky C (1958). "On the separation of the tryptophan synthetase of Escherichia coli into two protein components." Proc Natl Acad Sci U S A 44(12);1161-70. PMID: 16590328

Hutter86: Hutter R, Niederberger P, DeMoss JA (1986). "Tryptophan biosynthetic genes in eukaryotic microorganisms." Annu Rev Microbiol 40;55-77. PMID: 3535653

Hyde88: Hyde CC, Ahmed SA, Padlan EA, Miles EW, Davies DR (1988). "Three-dimensional structure of the tryptophan synthase alpha 2 beta 2 multienzyme complex from Salmonella typhimurium." J Biol Chem 263(33);17857-71. PMID: 3053720

Latendresse13: Latendresse M. (2013). "Computing Gibbs Free Energy of Compounds and Reactions in MetaCyc."

Woehl99: Woehl E, Dunn MF (1999). "Mechanisms of monovalent cation action in enzyme catalysis: the tryptophan synthase alpha-, beta-, and alpha beta-reactions." Biochemistry 38(22);7131-41. PMID: 10353823

Report Errors or Provide Feedback
Please cite the following article in publications resulting from the use of MetaCyc: Caspi et al, Nucleic Acids Research 42:D459-D471 2014
Page generated by Pathway Tools version 19.5 (software by SRI International) on Fri Feb 12, 2016, biocyc13.