L-tryptophan biosynthesis

MetaCyc:TRPSYN-PWY

L-tryptophan biosynthesis converts chorismate and L-glutamine to anthranilate, transfers a phosphoribosyl group from 5-phospho-alpha-D-ribose 1-diphosphate, isomerizes N-(5-phospho-beta-D-ribosyl)anthranilate to 1-(2-carboxyphenylamino)-1-deoxy-D-ribulose 5-phosphate, cyclizes that intermediate to (1S,2R)-1-C-(indol-3-yl)glycerol 3-phosphate, and condenses it with L-serine to make L-tryptophan.

Pathway type

amino acid biosynthesis

Organism scope

Escherichia coli NCBITaxon:562

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Pathway network

35 nodes · 48 asserted directed edges

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Reaction / activity
Chemical / cofactor
Protein / complex
Other participant
Solid arrow: mechanistic relation
Dashed arrow: membership, location or cofactor relation

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Components and activities

Declared biological components and source reaction directions
Node	Kind or role	Source direction
Escherichia coli `NCBITaxon:562`	taxon
anthranilate synthase `EC:4.1.3.27`	molecular activity
anthranilate phosphoribosyltransferase `EC:2.4.2.18`	molecular activity
phosphoribosylanthranilate isomerase `EC:5.3.1.24`	molecular activity
indole-3-glycerol-phosphate synthase `EC:4.1.1.48`	molecular activity
tryptophan synthase `EC:4.2.1.20`	molecular activity
chorismate `CHEBI:29748`	small molecule
L-glutamine `CHEBI:58359`	small molecule
anthranilate `CHEBI:16567`	small molecule
pyruvate `CHEBI:15361`	small molecule
L-glutamate `CHEBI:29985`	small molecule
H+ `CHEBI:15378`	small molecule
5-phospho-alpha-D-ribose 1-diphosphate `CHEBI:58017`	small molecule
N-(5-phospho-beta-D-ribosyl)anthranilate `CHEBI:18277`	small molecule
diphosphate `CHEBI:33019`	small molecule
1-(2-carboxyphenylamino)-1-deoxy-D-ribulose 5-phosphate `CHEBI:58613`	small molecule
(1S,2R)-1-C-(indol-3-yl)glycerol 3-phosphate `CHEBI:58866`	small molecule
CO2 `CHEBI:16526`	small molecule
H2O `CHEBI:15377`	small molecule
L-serine `CHEBI:33384`	small molecule
D-glyceraldehyde 3-phosphate `CHEBI:59776`	small molecule
L-tryptophan `CHEBI:57912`	small molecule
1H-indole `CHEBI:16881`	small molecule
Anthranilate synthase component 1 `UniProtKB:P00895`	protein
magnesium(2+) `CHEBI:18420`	cofactor
Bifunctional protein TrpGD `UniProtKB:P00904`	protein
Tryptophan biosynthesis protein TrpCF `UniProtKB:P00909`	protein
Tryptophan synthase alpha chain `UniProtKB:P0A877`	protein
Tryptophan synthase beta chain `UniProtKB:P0A879`	protein
pyridoxal 5'-phosphate(2-) `CHEBI:597326`	cofactor
anthranilate synthase reaction `RHEA:21733`	reaction	left to right
anthranilate phosphoribosyltransferase reaction `RHEA:11770`	reaction	right to left
phosphoribosylanthranilate isomerase reaction `RHEA:21541`	reaction	left to right
indole-3-glycerol-phosphate synthase reaction `RHEA:23477`	reaction	left to right
(1S,2R)-1-C-(indol-3-yl)glycerol 3-phosphate => indole + D-glyceraldehyde 3-phosphate `RHEA:14082`	reaction	left to right
indole + L-serine => L-tryptophan + H2O `RHEA:26435`	reaction	left to right

Mechanistic edges

Mechanistic edges and their cited evidence
Subject	Predicate and description	Object	Evidence
chorismate `CHEBI:29748`	consumes	anthranilate synthase reaction `RHEA:21733`	RHEA:21733 Source assertion: Rhea lists CHEBI:29748 on the substrates side of RHEA:21733 in this directed reaction. Source location `rdf:Description[@rdf:about='http://rdf.rhea-db.org/21733']/rh:substrates; rh:contains/rh:compound/rh:accession`
L-glutamine `CHEBI:58359`	consumes	anthranilate synthase reaction `RHEA:21733`	RHEA:21733 Source assertion: Rhea lists CHEBI:58359 on the substrates side of RHEA:21733 in this directed reaction. Source location `rdf:Description[@rdf:about='http://rdf.rhea-db.org/21733']/rh:substrates; rh:contains/rh:compound/rh:accession`
anthranilate synthase reaction `RHEA:21733`	produces	pyruvate `CHEBI:15361`	RHEA:21733 Source assertion: Rhea lists CHEBI:15361 on the products side of RHEA:21733 in this directed reaction. Source location `rdf:Description[@rdf:about='http://rdf.rhea-db.org/21733']/rh:products; rh:contains/rh:compound/rh:accession`
anthranilate synthase reaction `RHEA:21733`	produces	H+ `CHEBI:15378`	RHEA:21733 Source assertion: Rhea lists CHEBI:15378 on the products side of RHEA:21733 in this directed reaction. Source location `rdf:Description[@rdf:about='http://rdf.rhea-db.org/21733']/rh:products; rh:contains/rh:compound/rh:accession`
anthranilate synthase reaction `RHEA:21733`	produces	anthranilate `CHEBI:16567`	RHEA:21733 Source assertion: Rhea lists CHEBI:16567 on the products side of RHEA:21733 in this directed reaction. Source location `rdf:Description[@rdf:about='http://rdf.rhea-db.org/21733']/rh:products; rh:contains/rh:compound/rh:accession`
anthranilate synthase reaction `RHEA:21733`	produces	L-glutamate `CHEBI:29985`	RHEA:21733 Source assertion: Rhea lists CHEBI:29985 on the products side of RHEA:21733 in this directed reaction. Source location `rdf:Description[@rdf:about='http://rdf.rhea-db.org/21733']/rh:products; rh:contains/rh:compound/rh:accession`
anthranilate `CHEBI:16567`	consumes	anthranilate phosphoribosyltransferase reaction `RHEA:11770`	RHEA:11770 Source assertion: Rhea lists CHEBI:16567 on the substrates side of RHEA:11770 in this directed reaction. Source location `rdf:Description[@rdf:about='http://rdf.rhea-db.org/11770']/rh:substrates; rh:contains/rh:compound/rh:accession`
5-phospho-alpha-D-ribose 1-diphosphate `CHEBI:58017`	consumes	anthranilate phosphoribosyltransferase reaction `RHEA:11770`	RHEA:11770 Source assertion: Rhea lists CHEBI:58017 on the substrates side of RHEA:11770 in this directed reaction. Source location `rdf:Description[@rdf:about='http://rdf.rhea-db.org/11770']/rh:substrates; rh:contains/rh:compound/rh:accession`
anthranilate phosphoribosyltransferase reaction `RHEA:11770`	produces	N-(5-phospho-beta-D-ribosyl)anthranilate `CHEBI:18277`	RHEA:11770 Source assertion: Rhea lists CHEBI:18277 on the products side of RHEA:11770 in this directed reaction. Source location `rdf:Description[@rdf:about='http://rdf.rhea-db.org/11770']/rh:products; rh:contains/rh:compound/rh:accession`
anthranilate phosphoribosyltransferase reaction `RHEA:11770`	produces	diphosphate `CHEBI:33019`	RHEA:11770 Source assertion: Rhea lists CHEBI:33019 on the products side of RHEA:11770 in this directed reaction. Source location `rdf:Description[@rdf:about='http://rdf.rhea-db.org/11770']/rh:products; rh:contains/rh:compound/rh:accession`
N-(5-phospho-beta-D-ribosyl)anthranilate `CHEBI:18277`	consumes	phosphoribosylanthranilate isomerase reaction `RHEA:21541`	RHEA:21541 Source assertion: Rhea lists CHEBI:18277 on the substrates side of RHEA:21541 in this directed reaction. Source location `rdf:Description[@rdf:about='http://rdf.rhea-db.org/21541']/rh:substrates; rh:contains/rh:compound/rh:accession`
phosphoribosylanthranilate isomerase reaction `RHEA:21541`	produces	1-(2-carboxyphenylamino)-1-deoxy-D-ribulose 5-phosphate `CHEBI:58613`	RHEA:21541 Source assertion: Rhea lists CHEBI:58613 on the products side of RHEA:21541 in this directed reaction. Source location `rdf:Description[@rdf:about='http://rdf.rhea-db.org/21541']/rh:products; rh:contains/rh:compound/rh:accession`
H+ `CHEBI:15378`	consumes	indole-3-glycerol-phosphate synthase reaction `RHEA:23477`	RHEA:23477 Source assertion: Rhea lists CHEBI:15378 on the substrates side of RHEA:23477 in this directed reaction. Source location `rdf:Description[@rdf:about='http://rdf.rhea-db.org/23477']/rh:substrates; rh:contains/rh:compound/rh:accession`
1-(2-carboxyphenylamino)-1-deoxy-D-ribulose 5-phosphate `CHEBI:58613`	consumes	indole-3-glycerol-phosphate synthase reaction `RHEA:23477`	RHEA:23477 Source assertion: Rhea lists CHEBI:58613 on the substrates side of RHEA:23477 in this directed reaction. Source location `rdf:Description[@rdf:about='http://rdf.rhea-db.org/23477']/rh:substrates; rh:contains/rh:compound/rh:accession`
indole-3-glycerol-phosphate synthase reaction `RHEA:23477`	produces	H2O `CHEBI:15377`	RHEA:23477 Source assertion: Rhea lists CHEBI:15377 on the products side of RHEA:23477 in this directed reaction. Source location `rdf:Description[@rdf:about='http://rdf.rhea-db.org/23477']/rh:products; rh:contains/rh:compound/rh:accession`
indole-3-glycerol-phosphate synthase reaction `RHEA:23477`	produces	CO2 `CHEBI:16526`	RHEA:23477 Source assertion: Rhea lists CHEBI:16526 on the products side of RHEA:23477 in this directed reaction. Source location `rdf:Description[@rdf:about='http://rdf.rhea-db.org/23477']/rh:products; rh:contains/rh:compound/rh:accession`
indole-3-glycerol-phosphate synthase reaction `RHEA:23477`	produces	(1S,2R)-1-C-(indol-3-yl)glycerol 3-phosphate `CHEBI:58866`	RHEA:23477 Source assertion: Rhea lists CHEBI:58866 on the products side of RHEA:23477 in this directed reaction. Source location `rdf:Description[@rdf:about='http://rdf.rhea-db.org/23477']/rh:products; rh:contains/rh:compound/rh:accession`
(1S,2R)-1-C-(indol-3-yl)glycerol 3-phosphate `CHEBI:58866`	consumes	(1S,2R)-1-C-(indol-3-yl)glycerol 3-phosphate => indole + D-glyceraldehyde 3-phosphate `RHEA:14082`	RHEA:14082 Source assertion: Rhea lists CHEBI:58866 on the substrates side of RHEA:14082 in this directed reaction. Source location `rdf:Description[@rdf:about='http://rdf.rhea-db.org/14082']/rh:substrates; rh:contains/rh:compound/rh:accession`
(1S,2R)-1-C-(indol-3-yl)glycerol 3-phosphate => indole + D-glyceraldehyde 3-phosphate `RHEA:14082`	produces	1H-indole `CHEBI:16881`	RHEA:14082 Source assertion: Rhea lists CHEBI:16881 on the products side of RHEA:14082 in this directed reaction. Source location `rdf:Description[@rdf:about='http://rdf.rhea-db.org/14082']/rh:products; rh:contains/rh:compound/rh:accession`
(1S,2R)-1-C-(indol-3-yl)glycerol 3-phosphate => indole + D-glyceraldehyde 3-phosphate `RHEA:14082`	produces	D-glyceraldehyde 3-phosphate `CHEBI:59776`	RHEA:14082 Source assertion: Rhea lists CHEBI:59776 on the products side of RHEA:14082 in this directed reaction. Source location `rdf:Description[@rdf:about='http://rdf.rhea-db.org/14082']/rh:products; rh:contains/rh:compound/rh:accession`
1H-indole `CHEBI:16881`	consumes	indole + L-serine => L-tryptophan + H2O `RHEA:26435`	RHEA:26435 Source assertion: Rhea lists CHEBI:16881 on the substrates side of RHEA:26435 in this directed reaction. Source location `rdf:Description[@rdf:about='http://rdf.rhea-db.org/26435']/rh:substrates; rh:contains/rh:compound/rh:accession`
L-serine `CHEBI:33384`	consumes	indole + L-serine => L-tryptophan + H2O `RHEA:26435`	RHEA:26435 Source assertion: Rhea lists CHEBI:33384 on the substrates side of RHEA:26435 in this directed reaction. Source location `rdf:Description[@rdf:about='http://rdf.rhea-db.org/26435']/rh:substrates; rh:contains/rh:compound/rh:accession`
indole + L-serine => L-tryptophan + H2O `RHEA:26435`	produces	H2O `CHEBI:15377`	RHEA:26435 Source assertion: Rhea lists CHEBI:15377 on the products side of RHEA:26435 in this directed reaction. Source location `rdf:Description[@rdf:about='http://rdf.rhea-db.org/26435']/rh:products; rh:contains/rh:compound/rh:accession`
indole + L-serine => L-tryptophan + H2O `RHEA:26435`	produces	L-tryptophan `CHEBI:57912`	RHEA:26435 Source assertion: Rhea lists CHEBI:57912 on the products side of RHEA:26435 in this directed reaction. Source location `rdf:Description[@rdf:about='http://rdf.rhea-db.org/26435']/rh:products; rh:contains/rh:compound/rh:accession`
anthranilate synthase `EC:4.1.3.27`	catalyzes	anthranilate synthase reaction `RHEA:21733`	RHEA:21732 Source assertion: Rhea associates EC:4.1.3.27 with the reaction family containing RHEA:21733. Source location `rh:ec` PMID:4886289 Anthranilate synthetase, an enzyme specified by the tryptophan operon of Escherichia coli: purification and characterization of component I. Source location `PubMed ArticleTitle`
anthranilate phosphoribosyltransferase `EC:2.4.2.18`	catalyzes	anthranilate phosphoribosyltransferase reaction `RHEA:11770`	RHEA:11768 Source assertion: Rhea associates EC:2.4.2.18 with the reaction family containing RHEA:11770. Source location `rh:ec` PMID:4886290 Anthranilate synthetase, an enzyme specified by the tryptophan operon of Escherichia coli: Comparative studies on the complex and the subunits. Source location `PubMed ArticleTitle`
phosphoribosylanthranilate isomerase `EC:5.3.1.24`	catalyzes	phosphoribosylanthranilate isomerase reaction `RHEA:21541`	RHEA:21540 Source assertion: Rhea associates EC:5.3.1.24 with the reaction family containing RHEA:21541. Source location `rh:ec` PMID:3298981 Phosphoribosylanthranilate isomerase-indoleglycerol-phosphate synthase from Escherichia coli. Source location `PubMed ArticleTitle`
indole-3-glycerol-phosphate synthase `EC:4.1.1.48`	catalyzes	indole-3-glycerol-phosphate synthase reaction `RHEA:23477`	RHEA:23476 Source assertion: Rhea associates EC:4.1.1.48 with the reaction family containing RHEA:23477. Source location `rh:ec` PMID:5332729 Indole-3-glycerol phosphate synthetase of Escherichia coli, an enzyme of the tryptophan operon. Source location `PubMed ArticleTitle`
tryptophan synthase `EC:4.2.1.20`	catalyzes	(1S,2R)-1-C-(indol-3-yl)glycerol 3-phosphate => indole + D-glyceraldehyde 3-phosphate `RHEA:14082`	MetaCyc:TRPSYN-PWY Source assertion: The native pathway assigns EC:4.2.1.20 activity to the enzymatic step represented by RHEA:14082; this is a component step when the EC definition is an overall reaction. Source location `Pathway/reaction-layout; Reaction/enzymatic-reaction and component-reaction relationships` PMID:16590328 ON THE SEPARATION OF THE TRYPTOPHAN SYNTHETASE OF ESCHERICHIA COLI INTO TWO PROTEIN COMPONENTS. Source location `PubMed ArticleTitle`
tryptophan synthase `EC:4.2.1.20`	catalyzes	indole + L-serine => L-tryptophan + H2O `RHEA:26435`	MetaCyc:TRPSYN-PWY Source assertion: The native pathway assigns EC:4.2.1.20 activity to the enzymatic step represented by RHEA:26435; this is a component step when the EC definition is an overall reaction. Source location `Pathway/reaction-layout; Reaction/enzymatic-reaction and component-reaction relationships` PMID:16590328 ON THE SEPARATION OF THE TRYPTOPHAN SYNTHETASE OF ESCHERICHIA COLI INTO TWO PROTEIN COMPONENTS. Source location `PubMed ArticleTitle`
anthranilate phosphoribosyltransferase reaction `RHEA:11770`	precedes	phosphoribosylanthranilate isomerase reaction `RHEA:21541`	MetaCyc:TRPSYN-PWY Source assertion: MetaCyc pathway ordering places RHEA:11770 before RHEA:21541 in this pathway. Shared intermediate: CHEBI:18277. Source location `Pathway/reaction-ordering and reaction-layout; Rhea-to-MetaCyc cross-references`
(1S,2R)-1-C-(indol-3-yl)glycerol 3-phosphate => indole + D-glyceraldehyde 3-phosphate `RHEA:14082`	precedes	indole + L-serine => L-tryptophan + H2O `RHEA:26435`	MetaCyc:TRPSYN-PWY Source assertion: MetaCyc pathway ordering places RHEA:14082 before RHEA:26435 in this pathway. Shared intermediate: CHEBI:16881. Source location `Pathway/reaction-ordering and reaction-layout; Rhea-to-MetaCyc cross-references`
phosphoribosylanthranilate isomerase reaction `RHEA:21541`	precedes	indole-3-glycerol-phosphate synthase reaction `RHEA:23477`	MetaCyc:TRPSYN-PWY Source assertion: MetaCyc pathway ordering places RHEA:21541 before RHEA:23477 in this pathway. Shared intermediate: CHEBI:58613. Source location `Pathway/reaction-ordering and reaction-layout; Rhea-to-MetaCyc cross-references`
anthranilate synthase reaction `RHEA:21733`	precedes	anthranilate phosphoribosyltransferase reaction `RHEA:11770`	MetaCyc:TRPSYN-PWY Source assertion: MetaCyc pathway ordering places RHEA:21733 before RHEA:11770 in this pathway. Shared intermediate: CHEBI:16567. Source location `Pathway/reaction-ordering and reaction-layout; Rhea-to-MetaCyc cross-references`
indole-3-glycerol-phosphate synthase reaction `RHEA:23477`	precedes	(1S,2R)-1-C-(indol-3-yl)glycerol 3-phosphate => indole + D-glyceraldehyde 3-phosphate `RHEA:14082`	MetaCyc:TRPSYN-PWY Source assertion: MetaCyc pathway ordering places RHEA:23477 before RHEA:14082 in this pathway. Shared intermediate: CHEBI:58866. Source location `Pathway/reaction-ordering and reaction-layout; Rhea-to-MetaCyc cross-references`
Anthranilate synthase component 1 `UniProtKB:P00895`	enables	anthranilate synthase reaction `RHEA:21733`	UniProtKB:P00895 Source assertion: UniProt annotates UniProtKB:P00895 with catalytic activity for the reaction family of RHEA:21733. Annotation evidence: ECO:0000269; organism taxon: NCBITaxon:83333. Source location `comments[commentType='CATALYTIC ACTIVITY'].reaction.reactionCrossReferences`
L-tryptophan `CHEBI:57912`	inhibits	Anthranilate synthase component 1 `UniProtKB:P00895`	UniProtKB:P00895 Source assertion: UniProt activity-regulation annotation: Cooperatively feedback inhibited by tryptophan Source location `comments[commentType='ACTIVITY REGULATION'].texts`
Anthranilate synthase component 1 `UniProtKB:P00895`	has_cofactor	magnesium(2+) `CHEBI:18420`	UniProtKB:P00895 Source assertion: UniProt lists CHEBI:18420 as a cofactor of UniProtKB:P00895 (evidence: ECO:0000250). Binds 1 Mg(2+) ion per subunit. Source location `comments[commentType='COFACTOR'].cofactors and note`
Bifunctional protein TrpGD `UniProtKB:P00904`	enables	anthranilate synthase reaction `RHEA:21733`	UniProtKB:P00904 Source assertion: UniProt annotates UniProtKB:P00904 with catalytic activity for the reaction family of RHEA:21733. Annotation evidence: ECO:0000269; organism taxon: NCBITaxon:83333. Source location `comments[commentType='CATALYTIC ACTIVITY'].reaction.reactionCrossReferences`
Bifunctional protein TrpGD `UniProtKB:P00904`	enables	anthranilate phosphoribosyltransferase reaction `RHEA:11770`	UniProtKB:P00904 Source assertion: UniProt annotates UniProtKB:P00904 with catalytic activity for the reaction family of RHEA:11770. Annotation evidence: ECO:0000269; organism taxon: NCBITaxon:83333. Source location `comments[commentType='CATALYTIC ACTIVITY'].reaction.reactionCrossReferences`
L-tryptophan `CHEBI:57912`	inhibits	Bifunctional protein TrpGD `UniProtKB:P00904`	UniProtKB:P00904 Source assertion: UniProt activity-regulation annotation: Cooperatively feedback inhibited by tryptophan Source location `comments[commentType='ACTIVITY REGULATION'].texts`
Tryptophan biosynthesis protein TrpCF `UniProtKB:P00909`	enables	phosphoribosylanthranilate isomerase reaction `RHEA:21541`	UniProtKB:P00909 Source assertion: UniProt annotates UniProtKB:P00909 with catalytic activity for the reaction family of RHEA:21541. Annotation evidence: curated source annotation; organism taxon: NCBITaxon:83333. Source location `comments[commentType='CATALYTIC ACTIVITY'].reaction.reactionCrossReferences`
Tryptophan biosynthesis protein TrpCF `UniProtKB:P00909`	enables	indole-3-glycerol-phosphate synthase reaction `RHEA:23477`	UniProtKB:P00909 Source assertion: UniProt annotates UniProtKB:P00909 with catalytic activity for the reaction family of RHEA:23477. Annotation evidence: curated source annotation; organism taxon: NCBITaxon:83333. Source location `comments[commentType='CATALYTIC ACTIVITY'].reaction.reactionCrossReferences`
Tryptophan synthase alpha chain `UniProtKB:P0A877`	enables	(1S,2R)-1-C-(indol-3-yl)glycerol 3-phosphate => indole + D-glyceraldehyde 3-phosphate `RHEA:14082`	UniProtKB:P0A877 Source assertion: UniProt annotates UniProtKB:P0A877 with catalytic activity for the overall reaction containing the native MetaCyc enzymatic component RHEA:14082. Annotation evidence: ECO:0000255; organism taxon: NCBITaxon:83333. Source location `comments[commentType='CATALYTIC ACTIVITY'].reaction.reactionCrossReferences`
Tryptophan synthase alpha chain `UniProtKB:P0A877`	enables	indole + L-serine => L-tryptophan + H2O `RHEA:26435`	UniProtKB:P0A877 Source assertion: UniProt annotates UniProtKB:P0A877 with catalytic activity for the overall reaction containing the native MetaCyc enzymatic component RHEA:26435. Annotation evidence: ECO:0000255; organism taxon: NCBITaxon:83333. Source location `comments[commentType='CATALYTIC ACTIVITY'].reaction.reactionCrossReferences`
Tryptophan synthase beta chain `UniProtKB:P0A879`	enables	(1S,2R)-1-C-(indol-3-yl)glycerol 3-phosphate => indole + D-glyceraldehyde 3-phosphate `RHEA:14082`	UniProtKB:P0A879 Source assertion: UniProt annotates UniProtKB:P0A879 with catalytic activity for the overall reaction containing the native MetaCyc enzymatic component RHEA:14082. Annotation evidence: curated source annotation; organism taxon: NCBITaxon:83333. Source location `comments[commentType='CATALYTIC ACTIVITY'].reaction.reactionCrossReferences`
Tryptophan synthase beta chain `UniProtKB:P0A879`	enables	indole + L-serine => L-tryptophan + H2O `RHEA:26435`	UniProtKB:P0A879 Source assertion: UniProt annotates UniProtKB:P0A879 with catalytic activity for the overall reaction containing the native MetaCyc enzymatic component RHEA:26435. Annotation evidence: curated source annotation; organism taxon: NCBITaxon:83333. Source location `comments[commentType='CATALYTIC ACTIVITY'].reaction.reactionCrossReferences`
Tryptophan synthase beta chain `UniProtKB:P0A879`	has_cofactor	pyridoxal 5'-phosphate(2-) `CHEBI:597326`	UniProtKB:P0A879 Source assertion: UniProt lists CHEBI:597326 as a cofactor of UniProtKB:P0A879 (evidence: curated annotation). Source location `comments[commentType='COFACTOR'].cofactors and note`

References

MetaCyc:TRPSYN-PWY MetaCyc L-tryptophan biosynthesis pathway (source version: 22.5)
RHEA:21732 Rhea anthranilate synthase reaction (source version: 139)
RHEA:21733 Rhea biosynthetic anthranilate synthase direction (source version: 139)
RHEA:11768 Rhea anthranilate phosphoribosyltransferase reaction (source version: 139)
RHEA:11770 Rhea biosynthetic anthranilate phosphoribosyltransferase direction (source version: 139)
RHEA:21540 Rhea phosphoribosylanthranilate isomerase reaction (source version: 139)
RHEA:21541 Rhea phosphoribosylanthranilate isomerase direction (source version: 139)
RHEA:23476 Rhea indole-3-glycerol-phosphate synthase reaction (source version: 139)
RHEA:23477 Rhea indole-3-glycerol-phosphate-forming direction (source version: 139)
RHEA:10532 Rhea tryptophan synthase reaction (source version: 139)
RHEA:10533 Rhea L-tryptophan-forming tryptophan synthase direction (source version: 139)
PMID:4886289 Ito et al., Journal of Bacteriology, 1969
PMID:4886290 Ito and Yanofsky, Journal of Bacteriology, 1969
PMID:3298981 Kirschner et al., Methods in Enzymology, 1987
PMID:5332729 Creighton and Yanofsky, Journal of Biological Chemistry, 1966
PMID:16590328 Crawford and Yanofsky, Proceedings of the National Academy of Sciences, 1958
RHEA:14082 RHEA:14082 authority record (source version: 139)
RHEA:26435 RHEA:26435 authority record (source version: 139)
UniProtKB:P00895 UniProtKB:P00895 authority record (source version: 2026_03)
UniProtKB:P00904 UniProtKB:P00904 authority record (source version: 2026_03)
UniProtKB:P00909 UniProtKB:P00909 authority record (source version: 2026_03)
UniProtKB:P0A877 UniProtKB:P0A877 authority record (source version: 2026_03)
UniProtKB:P0A879 UniProtKB:P0A879 authority record (source version: 2026_03)

Curation history

2026-10-05T06:25:52Z codex
- EDIT — Review causal chemistry and add sourced molecular context
  Reviewed the entire record against MetaCyc 22.5 native pathway XML (including nested pathways), Rhea 139 explicit sides and directions, ENZYME 02-Sep-2026, PubMed records, and reviewed UniProt 2026_03 annotations within the record's taxon scope. Replaced generated structured-source quotations with source_assertion and source_locator. Typed molecular activities and participants. Reaction count 5 to 6; 0 directed-ID corrections; 5 protein annotations, 2 cofactor annotations and 0 sourced locations. All Rhea reaction substrate/product sets checked against independent Rhea authority; native pathway leaf coverage and source exceptions recorded in reports/causal_graph_review/metacyc-review.json. Full source URLs, versions and byte hashes are in metacyc-sources.json. All 50 MetaCyc records passed native schema validation; six targeted chemistry/evidence regression tests passed. Missing protein or cofactor annotations are not treated as biological absence; qualifications and exclusions are preserved in the ledger. Expanded combined reaction steps: RHEA:10533.
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