Mycothiol biosynthesis

Reactome:R-MTU-879299

Cytosolic mycothiol synthesis in Mycobacterium tuberculosis links Ino1, MshA, an unresolved phosphatase, MshB, MshC and MshD. Mca supplies a minor alternative deacetylase route. The source models zinc-containing Ino1, Mca and MshC assemblies; Mca metal occupancy depends on oxygen conditions. ImpC is not assigned as the unresolved phosphatase because later experiments identify it as histidinol-phosphatase.

Pathway type

biopax pathway

Organism scope

Mycobacterium tuberculosis NCBITaxon:1773

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Pathway network

39 nodes · 78 asserted directed edges

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Reaction / activity
Chemical / cofactor
Protein / complex
Cell / process context
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
Mycobacterium tuberculosis `NCBITaxon:1773`	taxon
Zn2+ `CHEBI:29105`	cofactor
UDP-N-acetyl-alpha-D-glucosamine(2-) `CHEBI:57705`	small molecule
UDP(3-) `CHEBI:58223`	small molecule
H2O `CHEBI:15377`	small molecule
Pi `CHEBI:43474`	small molecule
GlcNAc-Ins `CHEBI:52442`	small molecule
L-cysteine zwitterion `CHEBI:35235`	small molecule
ATP(4-) `CHEBI:30616`	small molecule
adenosine 5'-monophosphate(2-) `CHEBI:456215`	small molecule
diphosphate(3-) `CHEBI:33019`	small molecule
acetyl-CoA(4-) `CHEBI:57288`	small molecule
coenzyme A(4-) `CHEBI:57287`	small molecule
mycothiol `CHEBI:16768`	small molecule
Ino1 `UniProtKB:P9WKI1`	protein
MshA `UniProtKB:P9WMY7`	protein
mca `UniProtKB:P9WJN1`	protein
MshC `UniProtKB:P9WJM9`	protein
MshD `UniProtKB:P9WJM7`	protein
Ino1-Zn2+ `Reactome:R-MTU-879258`	complex
mca:Zn2+ `Reactome:R-MTU-879260`	complex
MshC-Zn2+ `Reactome:R-MTU-879241`	complex
cytosol `GO:0005829`	cellular component
D-glucopyranose 6-phosphate(2-) `CHEBI:61548`	small molecule
1D-myo-inositol 3-phosphate(2-) `CHEBI:58401`	small molecule
1D-myo-inositol 2-acetamido-2-deoxy-alpha-D-glucopyranoside 3-phosphate(2-) `CHEBI:58892`	small molecule
hydron `CHEBI:15378`	small molecule
1D-myo-inositol 2-ammonio-2-deoxy-alpha-D-glucopyranoside `CHEBI:58886`	small molecule
1D-myo-inositol 2-(L-cysteiniumylamino)-2-deoxy-alpha-D-glucopyranoside `CHEBI:58887`	small molecule
MshB `UniProtKB:P9WJN3`	protein
acetate `CHEBI:30089`	small molecule
NAD(1-) `CHEBI:57540`	cofactor
iron(2+) `CHEBI:29033`	cofactor
glucose-6-phosphate is converted to inositol-1-phosphate `Reactome:R-MTU-879331`	molecular activity	left to right
acetylglucosamine is transferred from UDP-GlcNAc onto inositol-1-phosphate `Reactome:R-MTU-879298`	molecular activity	left to right
acetylglucosamine-inositol-phosphate is dephosphorylated `Reactome:R-MTU-879274`	molecular activity	left to right
acetylglucosamine-inositol is deacetylated by Mca `Reactome:R-MTU-879327`	molecular activity	left to right
glucosaminyl-inositol and cysteine are ligated to desacetylmycothiol `Reactome:R-MTU-879319`	molecular activity	left to right
desacetylmycothiol is acetylated to mycothiol using acetyl-CoA `Reactome:R-MTU-879248`	molecular activity	left to right
1D-myo-inositol 2-acetamido-2-deoxy-alpha-D-glucopyranoside + H2O = 1D-myo-inositol 2-amino-2-deoxy-alpha-D-glucopyranoside + acetate `RHEA:26180`	molecular activity	left to right

Mechanistic edges

Mechanistic edges and their cited evidence
Subject	Predicate and description	Object	Evidence
glucose-6-phosphate is converted to inositol-1-phosphate `Reactome:R-MTU-879331`	occurs_in	cytosol `GO:0005829`	Reactome:R-MTU-879299 Source assertion: The physical participants of BioPAX BiochemicalReaction1 are assigned to the cytosol. Source location `#BiochemicalReaction1; participating physicalEntity/bp:cellularLocation/#CellularLocationVocabulary1`
acetylglucosamine is transferred from UDP-GlcNAc onto inositol-1-phosphate `Reactome:R-MTU-879298`	occurs_in	cytosol `GO:0005829`	Reactome:R-MTU-879299 Source assertion: The physical participants of BioPAX BiochemicalReaction2 are assigned to the cytosol. Source location `#BiochemicalReaction2; participating physicalEntity/bp:cellularLocation/#CellularLocationVocabulary1`
1D-myo-inositol 2-acetamido-2-deoxy-alpha-D-glucopyranoside 3-phosphate(2-) `CHEBI:58892`	consumes Chemical form reconciled with the curated MshA/MshB/MshC reaction definitions; native BioPAX topology retained.	acetylglucosamine-inositol-phosphate is dephosphorylated `Reactome:R-MTU-879274`	Reactome:R-MTU-879299 Source assertion: BioPAX BiochemicalReaction3 lists GlcNAc-Ins-P on its left side with LEFT-TO-RIGHT conversionDirection. Source location `#BiochemicalReaction3/bp:left/#SmallMolecule5`
H2O `CHEBI:15377`	consumes	acetylglucosamine-inositol-phosphate is dephosphorylated `Reactome:R-MTU-879274`	Reactome:R-MTU-879299 Source assertion: BioPAX BiochemicalReaction3 lists H2O on its left side with LEFT-TO-RIGHT conversionDirection. Source location `#BiochemicalReaction3/bp:left/#SmallMolecule7`
acetylglucosamine-inositol-phosphate is dephosphorylated `Reactome:R-MTU-879274`	produces	Pi `CHEBI:43474`	Reactome:R-MTU-879299 Source assertion: BioPAX BiochemicalReaction3 lists Pi on its right side with LEFT-TO-RIGHT conversionDirection. Source location `#BiochemicalReaction3/bp:right/#SmallMolecule8`
acetylglucosamine-inositol-phosphate is dephosphorylated `Reactome:R-MTU-879274`	produces	GlcNAc-Ins `CHEBI:52442`	Reactome:R-MTU-879299 Source assertion: BioPAX BiochemicalReaction3 lists GlcNAc-Ins on its right side with LEFT-TO-RIGHT conversionDirection. Source location `#BiochemicalReaction3/bp:right/#SmallMolecule9`
acetylglucosamine-inositol-phosphate is dephosphorylated `Reactome:R-MTU-879274`	occurs_in	cytosol `GO:0005829`	Reactome:R-MTU-879299 Source assertion: The physical participants of BioPAX BiochemicalReaction3 are assigned to the cytosol. Source location `#BiochemicalReaction3; participating physicalEntity/bp:cellularLocation/#CellularLocationVocabulary1`
H2O `CHEBI:15377`	consumes	acetylglucosamine-inositol is deacetylated by Mca `Reactome:R-MTU-879327`	Reactome:R-MTU-879299 Source assertion: BioPAX BiochemicalReaction4 lists H2O on its left side with LEFT-TO-RIGHT conversionDirection. Source location `#BiochemicalReaction4/bp:left/#SmallMolecule7`
GlcNAc-Ins `CHEBI:52442`	consumes	acetylglucosamine-inositol is deacetylated by Mca `Reactome:R-MTU-879327`	Reactome:R-MTU-879299 Source assertion: BioPAX BiochemicalReaction4 lists GlcNAc-Ins on its left side with LEFT-TO-RIGHT conversionDirection. Source location `#BiochemicalReaction4/bp:left/#SmallMolecule9`
acetylglucosamine-inositol is deacetylated by Mca `Reactome:R-MTU-879327`	produces Chemical form reconciled with the curated MshA/MshB/MshC reaction definitions; native BioPAX topology retained.	1D-myo-inositol 2-ammonio-2-deoxy-alpha-D-glucopyranoside `CHEBI:58886`	Reactome:R-MTU-879299 Source assertion: BioPAX BiochemicalReaction4 lists GlcNI on its right side with LEFT-TO-RIGHT conversionDirection. Source location `#BiochemicalReaction4/bp:right/#SmallMolecule10`
acetylglucosamine-inositol is deacetylated by Mca `Reactome:R-MTU-879327`	produces Chemical form reconciled with the curated MshA/MshB/MshC reaction definitions; native BioPAX topology retained.	acetate `CHEBI:30089`	Reactome:R-MTU-879299 Source assertion: BioPAX BiochemicalReaction4 lists CH3COO- on its right side with LEFT-TO-RIGHT conversionDirection. Source location `#BiochemicalReaction4/bp:right/#SmallMolecule11`
acetylglucosamine-inositol is deacetylated by Mca `Reactome:R-MTU-879327`	occurs_in	cytosol `GO:0005829`	Reactome:R-MTU-879299 Source assertion: The physical participants of BioPAX BiochemicalReaction4 are assigned to the cytosol. Source location `#BiochemicalReaction4; participating physicalEntity/bp:cellularLocation/#CellularLocationVocabulary1`
glucosaminyl-inositol and cysteine are ligated to desacetylmycothiol `Reactome:R-MTU-879319`	occurs_in	cytosol `GO:0005829`	Reactome:R-MTU-879299 Source assertion: The physical participants of BioPAX BiochemicalReaction5 are assigned to the cytosol. Source location `#BiochemicalReaction5; participating physicalEntity/bp:cellularLocation/#CellularLocationVocabulary1`
desacetylmycothiol is acetylated to mycothiol using acetyl-CoA `Reactome:R-MTU-879248`	occurs_in	cytosol `GO:0005829`	Reactome:R-MTU-879299 Source assertion: The physical participants of BioPAX BiochemicalReaction6 are assigned to the cytosol. Source location `#BiochemicalReaction6; participating physicalEntity/bp:cellularLocation/#CellularLocationVocabulary1`
Ino1-Zn2+ `Reactome:R-MTU-879258`	catalyzes	glucose-6-phosphate is converted to inositol-1-phosphate `Reactome:R-MTU-879331`	Reactome:R-MTU-879299 Source assertion: BioPAX Catalysis1 identifies Ino1-Zn2+ as the controller of BiochemicalReaction1. Source location `#Catalysis1/bp:controller/#Complex1; bp:controlled/#BiochemicalReaction1`
MshA `UniProtKB:P9WMY7`	catalyzes	acetylglucosamine is transferred from UDP-GlcNAc onto inositol-1-phosphate `Reactome:R-MTU-879298`	Reactome:R-MTU-879299 Source assertion: BioPAX Catalysis2 identifies MshA as the controller of BiochemicalReaction2. Source location `#Catalysis2/bp:controller/#Protein2; bp:controlled/#BiochemicalReaction2`
mca:Zn2+ `Reactome:R-MTU-879260`	catalyzes The native zinc-bound Mca assembly represents the aerobic purified form; Fe2+ is favored under physiological anaerobic conditions (PMID:26044118).	acetylglucosamine-inositol is deacetylated by Mca `Reactome:R-MTU-879327`	Reactome:R-MTU-879299 Source assertion: BioPAX Catalysis4 identifies mca:Zn2+ as the controller of BiochemicalReaction4. Source location `#Catalysis4/bp:controller/#Complex2; bp:controlled/#BiochemicalReaction4`
MshC-Zn2+ `Reactome:R-MTU-879241`	catalyzes	glucosaminyl-inositol and cysteine are ligated to desacetylmycothiol `Reactome:R-MTU-879319`	Reactome:R-MTU-879299 Source assertion: BioPAX Catalysis5 identifies MshC-Zn2+ as the controller of BiochemicalReaction5. Source location `#Catalysis5/bp:controller/#Complex3; bp:controlled/#BiochemicalReaction5`
MshD `UniProtKB:P9WJM7`	catalyzes	desacetylmycothiol is acetylated to mycothiol using acetyl-CoA `Reactome:R-MTU-879248`	Reactome:R-MTU-879299 Source assertion: BioPAX Catalysis6 identifies MshD as the controller of BiochemicalReaction6. Source location `#Catalysis6/bp:controller/#Protein6; bp:controlled/#BiochemicalReaction6`
Zn2+ `CHEBI:29105`	located_in	cytosol `GO:0005829`	Reactome:R-MTU-879299 Source assertion: BioPAX SmallMolecule3 assigns Zn2+ to the cytosol. Source location `#SmallMolecule3/bp:cellularLocation/#CellularLocationVocabulary1`
UDP-N-acetyl-alpha-D-glucosamine(2-) `CHEBI:57705`	located_in	cytosol `GO:0005829`	Reactome:R-MTU-879299 Source assertion: BioPAX SmallMolecule4 assigns UDP-GlcNAc to the cytosol. Source location `#SmallMolecule4/bp:cellularLocation/#CellularLocationVocabulary1`
1D-myo-inositol 2-acetamido-2-deoxy-alpha-D-glucopyranoside 3-phosphate(2-) `CHEBI:58892`	located_in Chemical form reconciled with the curated MshA/MshB/MshC reaction definitions; native BioPAX topology retained.	cytosol `GO:0005829`	Reactome:R-MTU-879299 Source assertion: BioPAX SmallMolecule5 assigns GlcNAc-Ins-P to the cytosol. Source location `#SmallMolecule5/bp:cellularLocation/#CellularLocationVocabulary1`
UDP(3-) `CHEBI:58223`	located_in	cytosol `GO:0005829`	Reactome:R-MTU-879299 Source assertion: BioPAX SmallMolecule6 assigns UDP to the cytosol. Source location `#SmallMolecule6/bp:cellularLocation/#CellularLocationVocabulary1`
H2O `CHEBI:15377`	located_in	cytosol `GO:0005829`	Reactome:R-MTU-879299 Source assertion: BioPAX SmallMolecule7 assigns H2O to the cytosol. Source location `#SmallMolecule7/bp:cellularLocation/#CellularLocationVocabulary1`
Pi `CHEBI:43474`	located_in	cytosol `GO:0005829`	Reactome:R-MTU-879299 Source assertion: BioPAX SmallMolecule8 assigns Pi to the cytosol. Source location `#SmallMolecule8/bp:cellularLocation/#CellularLocationVocabulary1`
GlcNAc-Ins `CHEBI:52442`	located_in	cytosol `GO:0005829`	Reactome:R-MTU-879299 Source assertion: BioPAX SmallMolecule9 assigns GlcNAc-Ins to the cytosol. Source location `#SmallMolecule9/bp:cellularLocation/#CellularLocationVocabulary1`
1D-myo-inositol 2-ammonio-2-deoxy-alpha-D-glucopyranoside `CHEBI:58886`	located_in Chemical form reconciled with the curated MshA/MshB/MshC reaction definitions; native BioPAX topology retained.	cytosol `GO:0005829`	Reactome:R-MTU-879299 Source assertion: BioPAX SmallMolecule10 assigns GlcNI to the cytosol. Source location `#SmallMolecule10/bp:cellularLocation/#CellularLocationVocabulary1`
acetate `CHEBI:30089`	located_in Chemical form reconciled with the curated MshA/MshB/MshC reaction definitions; native BioPAX topology retained.	cytosol `GO:0005829`	Reactome:R-MTU-879299 Source assertion: BioPAX SmallMolecule11 assigns CH3COO- to the cytosol. Source location `#SmallMolecule11/bp:cellularLocation/#CellularLocationVocabulary1`
L-cysteine zwitterion `CHEBI:35235`	located_in	cytosol `GO:0005829`	Reactome:R-MTU-879299 Source assertion: BioPAX SmallMolecule12 assigns L-Cys to the cytosol. Source location `#SmallMolecule12/bp:cellularLocation/#CellularLocationVocabulary1`
ATP(4-) `CHEBI:30616`	located_in	cytosol `GO:0005829`	Reactome:R-MTU-879299 Source assertion: BioPAX SmallMolecule13 assigns ATP to the cytosol. Source location `#SmallMolecule13/bp:cellularLocation/#CellularLocationVocabulary1`
adenosine 5'-monophosphate(2-) `CHEBI:456215`	located_in	cytosol `GO:0005829`	Reactome:R-MTU-879299 Source assertion: BioPAX SmallMolecule14 assigns AMP to the cytosol. Source location `#SmallMolecule14/bp:cellularLocation/#CellularLocationVocabulary1`
diphosphate(3-) `CHEBI:33019`	located_in	cytosol `GO:0005829`	Reactome:R-MTU-879299 Source assertion: BioPAX SmallMolecule16 assigns PPi to the cytosol. Source location `#SmallMolecule16/bp:cellularLocation/#CellularLocationVocabulary1`
acetyl-CoA(4-) `CHEBI:57288`	located_in	cytosol `GO:0005829`	Reactome:R-MTU-879299 Source assertion: BioPAX SmallMolecule17 assigns Ac-CoA to the cytosol. Source location `#SmallMolecule17/bp:cellularLocation/#CellularLocationVocabulary1`
coenzyme A(4-) `CHEBI:57287`	located_in	cytosol `GO:0005829`	Reactome:R-MTU-879299 Source assertion: BioPAX SmallMolecule18 assigns CoA-SH to the cytosol. Source location `#SmallMolecule18/bp:cellularLocation/#CellularLocationVocabulary1`
mycothiol `CHEBI:16768`	located_in	cytosol `GO:0005829`	Reactome:R-MTU-879299 Source assertion: BioPAX SmallMolecule19 assigns MSH to the cytosol. Source location `#SmallMolecule19/bp:cellularLocation/#CellularLocationVocabulary1`
Ino1 `UniProtKB:P9WKI1`	located_in	cytosol `GO:0005829`	Reactome:R-MTU-879299 Source assertion: BioPAX Protein1 assigns Ino1 to the cytosol. Source location `#Protein1/bp:cellularLocation/#CellularLocationVocabulary1`
MshA `UniProtKB:P9WMY7`	located_in	cytosol `GO:0005829`	Reactome:R-MTU-879299 Source assertion: BioPAX Protein2 assigns MshA to the cytosol. Source location `#Protein2/bp:cellularLocation/#CellularLocationVocabulary1`
mca `UniProtKB:P9WJN1`	located_in	cytosol `GO:0005829`	Reactome:R-MTU-879299 Source assertion: BioPAX Protein4 assigns mca to the cytosol. Source location `#Protein4/bp:cellularLocation/#CellularLocationVocabulary1`
MshC `UniProtKB:P9WJM9`	located_in	cytosol `GO:0005829`	Reactome:R-MTU-879299 Source assertion: BioPAX Protein5 assigns MshC to the cytosol. Source location `#Protein5/bp:cellularLocation/#CellularLocationVocabulary1`
MshD `UniProtKB:P9WJM7`	located_in	cytosol `GO:0005829`	Reactome:R-MTU-879299 Source assertion: BioPAX Protein6 assigns MshD to the cytosol. Source location `#Protein6/bp:cellularLocation/#CellularLocationVocabulary1`
Ino1-Zn2+ `Reactome:R-MTU-879258`	located_in	cytosol `GO:0005829`	Reactome:R-MTU-879299 Source assertion: BioPAX Complex1 assigns Ino1-Zn2+ to the cytosol. Source location `#Complex1/bp:cellularLocation/#CellularLocationVocabulary1`
Ino1-Zn2+ `Reactome:R-MTU-879258`	has_part	Ino1 `UniProtKB:P9WKI1`	Reactome:R-MTU-879299 Source assertion: BioPAX Complex1 includes Ino1 as a component of Ino1-Zn2+. Source location `#Complex1/bp:component/#Protein1`
Ino1-Zn2+ `Reactome:R-MTU-879258`	has_part	Zn2+ `CHEBI:29105`	Reactome:R-MTU-879299 Source assertion: BioPAX Complex1 includes Zn2+ as a component of Ino1-Zn2+. Source location `#Complex1/bp:component/#SmallMolecule3`
mca:Zn2+ `Reactome:R-MTU-879260`	located_in	cytosol `GO:0005829`	Reactome:R-MTU-879299 Source assertion: BioPAX Complex2 assigns mca:Zn2+ to the cytosol. Source location `#Complex2/bp:cellularLocation/#CellularLocationVocabulary1`
mca:Zn2+ `Reactome:R-MTU-879260`	has_part	Zn2+ `CHEBI:29105`	Reactome:R-MTU-879299 Source assertion: BioPAX Complex2 includes Zn2+ as a component of mca:Zn2+. Source location `#Complex2/bp:component/#SmallMolecule3`
mca:Zn2+ `Reactome:R-MTU-879260`	has_part	mca `UniProtKB:P9WJN1`	Reactome:R-MTU-879299 Source assertion: BioPAX Complex2 includes mca as a component of mca:Zn2+. Source location `#Complex2/bp:component/#Protein4`
MshC-Zn2+ `Reactome:R-MTU-879241`	located_in	cytosol `GO:0005829`	Reactome:R-MTU-879299 Source assertion: BioPAX Complex3 assigns MshC-Zn2+ to the cytosol. Source location `#Complex3/bp:cellularLocation/#CellularLocationVocabulary1`
MshC-Zn2+ `Reactome:R-MTU-879241`	has_part	MshC `UniProtKB:P9WJM9`	Reactome:R-MTU-879299 Source assertion: BioPAX Complex3 includes MshC as a component of MshC-Zn2+. Source location `#Complex3/bp:component/#Protein5`
MshC-Zn2+ `Reactome:R-MTU-879241`	has_part	Zn2+ `CHEBI:29105`	Reactome:R-MTU-879299 Source assertion: BioPAX Complex3 includes Zn2+ as a component of MshC-Zn2+. Source location `#Complex3/bp:component/#SmallMolecule3`
D-glucopyranose 6-phosphate(2-) `CHEBI:61548`	consumes	glucose-6-phosphate is converted to inositol-1-phosphate `Reactome:R-MTU-879331`	UniProtKB:P9WKI1 Source assertion: RHEA:10716 identifies CHEBI:61548 as a substrate. Source location `comments[commentType=CATALYTIC ACTIVITY].reaction[RHEA:10716]`
glucose-6-phosphate is converted to inositol-1-phosphate `Reactome:R-MTU-879331`	produces	1D-myo-inositol 3-phosphate(2-) `CHEBI:58401`	UniProtKB:P9WKI1 Source assertion: RHEA:10716 identifies CHEBI:58401 as a product. Source location `comments[commentType=CATALYTIC ACTIVITY].reaction[RHEA:10716]`
1D-myo-inositol 3-phosphate(2-) `CHEBI:58401`	consumes	acetylglucosamine is transferred from UDP-GlcNAc onto inositol-1-phosphate `Reactome:R-MTU-879298`	UniProtKB:P9WMY7 Source assertion: RHEA:26188 identifies CHEBI:58401 as a substrate. Source location `comments[commentType=CATALYTIC ACTIVITY].reaction[RHEA:26188]`
UDP-N-acetyl-alpha-D-glucosamine(2-) `CHEBI:57705`	consumes	acetylglucosamine is transferred from UDP-GlcNAc onto inositol-1-phosphate `Reactome:R-MTU-879298`	UniProtKB:P9WMY7 Source assertion: RHEA:26188 identifies CHEBI:57705 as a substrate. Source location `comments[commentType=CATALYTIC ACTIVITY].reaction[RHEA:26188]`
acetylglucosamine is transferred from UDP-GlcNAc onto inositol-1-phosphate `Reactome:R-MTU-879298`	produces	1D-myo-inositol 2-acetamido-2-deoxy-alpha-D-glucopyranoside 3-phosphate(2-) `CHEBI:58892`	UniProtKB:P9WMY7 Source assertion: RHEA:26188 identifies CHEBI:58892 as a product. Source location `comments[commentType=CATALYTIC ACTIVITY].reaction[RHEA:26188]`
acetylglucosamine is transferred from UDP-GlcNAc onto inositol-1-phosphate `Reactome:R-MTU-879298`	produces	UDP(3-) `CHEBI:58223`	UniProtKB:P9WMY7 Source assertion: RHEA:26188 identifies CHEBI:58223 as a product. Source location `comments[commentType=CATALYTIC ACTIVITY].reaction[RHEA:26188]`
acetylglucosamine is transferred from UDP-GlcNAc onto inositol-1-phosphate `Reactome:R-MTU-879298`	produces	hydron `CHEBI:15378`	UniProtKB:P9WMY7 Source assertion: RHEA:26188 identifies CHEBI:15378 as a product. Source location `comments[commentType=CATALYTIC ACTIVITY].reaction[RHEA:26188]`
1D-myo-inositol 2-ammonio-2-deoxy-alpha-D-glucopyranoside `CHEBI:58886`	consumes	glucosaminyl-inositol and cysteine are ligated to desacetylmycothiol `Reactome:R-MTU-879319`	UniProtKB:P9WJM9 Source assertion: RHEA:26176 identifies CHEBI:58886 as a substrate. Source location `comments[commentType=CATALYTIC ACTIVITY].reaction[RHEA:26176]`
L-cysteine zwitterion `CHEBI:35235`	consumes	glucosaminyl-inositol and cysteine are ligated to desacetylmycothiol `Reactome:R-MTU-879319`	UniProtKB:P9WJM9 Source assertion: RHEA:26176 identifies CHEBI:35235 as a substrate. Source location `comments[commentType=CATALYTIC ACTIVITY].reaction[RHEA:26176]`
ATP(4-) `CHEBI:30616`	consumes	glucosaminyl-inositol and cysteine are ligated to desacetylmycothiol `Reactome:R-MTU-879319`	UniProtKB:P9WJM9 Source assertion: RHEA:26176 identifies CHEBI:30616 as a substrate. Source location `comments[commentType=CATALYTIC ACTIVITY].reaction[RHEA:26176]`
glucosaminyl-inositol and cysteine are ligated to desacetylmycothiol `Reactome:R-MTU-879319`	produces	1D-myo-inositol 2-(L-cysteiniumylamino)-2-deoxy-alpha-D-glucopyranoside `CHEBI:58887`	UniProtKB:P9WJM9 Source assertion: RHEA:26176 identifies CHEBI:58887 as a product. Source location `comments[commentType=CATALYTIC ACTIVITY].reaction[RHEA:26176]`
glucosaminyl-inositol and cysteine are ligated to desacetylmycothiol `Reactome:R-MTU-879319`	produces	adenosine 5'-monophosphate(2-) `CHEBI:456215`	UniProtKB:P9WJM9 Source assertion: RHEA:26176 identifies CHEBI:456215 as a product. Source location `comments[commentType=CATALYTIC ACTIVITY].reaction[RHEA:26176]`
glucosaminyl-inositol and cysteine are ligated to desacetylmycothiol `Reactome:R-MTU-879319`	produces	diphosphate(3-) `CHEBI:33019`	UniProtKB:P9WJM9 Source assertion: RHEA:26176 identifies CHEBI:33019 as a product. Source location `comments[commentType=CATALYTIC ACTIVITY].reaction[RHEA:26176]`
glucosaminyl-inositol and cysteine are ligated to desacetylmycothiol `Reactome:R-MTU-879319`	produces	hydron `CHEBI:15378`	UniProtKB:P9WJM9 Source assertion: RHEA:26176 identifies CHEBI:15378 as a product. Source location `comments[commentType=CATALYTIC ACTIVITY].reaction[RHEA:26176]`
1D-myo-inositol 2-(L-cysteiniumylamino)-2-deoxy-alpha-D-glucopyranoside `CHEBI:58887`	consumes	desacetylmycothiol is acetylated to mycothiol using acetyl-CoA `Reactome:R-MTU-879248`	UniProtKB:P9WJM7 Source assertion: RHEA:26172 identifies CHEBI:58887 as a substrate. Source location `comments[commentType=CATALYTIC ACTIVITY].reaction[RHEA:26172]`
acetyl-CoA(4-) `CHEBI:57288`	consumes	desacetylmycothiol is acetylated to mycothiol using acetyl-CoA `Reactome:R-MTU-879248`	UniProtKB:P9WJM7 Source assertion: RHEA:26172 identifies CHEBI:57288 as a substrate. Source location `comments[commentType=CATALYTIC ACTIVITY].reaction[RHEA:26172]`
desacetylmycothiol is acetylated to mycothiol using acetyl-CoA `Reactome:R-MTU-879248`	produces	mycothiol `CHEBI:16768`	UniProtKB:P9WJM7 Source assertion: RHEA:26172 identifies CHEBI:16768 as a product. Source location `comments[commentType=CATALYTIC ACTIVITY].reaction[RHEA:26172]`
desacetylmycothiol is acetylated to mycothiol using acetyl-CoA `Reactome:R-MTU-879248`	produces	coenzyme A(4-) `CHEBI:57287`	UniProtKB:P9WJM7 Source assertion: RHEA:26172 identifies CHEBI:57287 as a product. Source location `comments[commentType=CATALYTIC ACTIVITY].reaction[RHEA:26172]`
desacetylmycothiol is acetylated to mycothiol using acetyl-CoA `Reactome:R-MTU-879248`	produces	hydron `CHEBI:15378`	UniProtKB:P9WJM7 Source assertion: RHEA:26172 identifies CHEBI:15378 as a product. Source location `comments[commentType=CATALYTIC ACTIVITY].reaction[RHEA:26172]`
GlcNAc-Ins `CHEBI:52442`	consumes	1D-myo-inositol 2-acetamido-2-deoxy-alpha-D-glucopyranoside + H2O = 1D-myo-inositol 2-amino-2-deoxy-alpha-D-glucopyranoside + acetate `RHEA:26180`	UniProtKB:P9WJN3 Source assertion: MshB catalyzes GlcNAc-Ins deacetylation to glucosaminyl-inositol and acetate (RHEA:26180). Source location `comments[commentType=CATALYTIC ACTIVITY].reaction[RHEA:26180]`
H2O `CHEBI:15377`	consumes	1D-myo-inositol 2-acetamido-2-deoxy-alpha-D-glucopyranoside + H2O = 1D-myo-inositol 2-amino-2-deoxy-alpha-D-glucopyranoside + acetate `RHEA:26180`	UniProtKB:P9WJN3 Source assertion: MshB catalyzes GlcNAc-Ins deacetylation to glucosaminyl-inositol and acetate (RHEA:26180). Source location `comments[commentType=CATALYTIC ACTIVITY].reaction[RHEA:26180]`
1D-myo-inositol 2-acetamido-2-deoxy-alpha-D-glucopyranoside + H2O = 1D-myo-inositol 2-amino-2-deoxy-alpha-D-glucopyranoside + acetate `RHEA:26180`	produces	1D-myo-inositol 2-ammonio-2-deoxy-alpha-D-glucopyranoside `CHEBI:58886`	UniProtKB:P9WJN3 Source assertion: MshB catalyzes GlcNAc-Ins deacetylation to glucosaminyl-inositol and acetate (RHEA:26180). Source location `comments[commentType=CATALYTIC ACTIVITY].reaction[RHEA:26180]`
1D-myo-inositol 2-acetamido-2-deoxy-alpha-D-glucopyranoside + H2O = 1D-myo-inositol 2-amino-2-deoxy-alpha-D-glucopyranoside + acetate `RHEA:26180`	produces	acetate `CHEBI:30089`	UniProtKB:P9WJN3 Source assertion: MshB catalyzes GlcNAc-Ins deacetylation to glucosaminyl-inositol and acetate (RHEA:26180). Source location `comments[commentType=CATALYTIC ACTIVITY].reaction[RHEA:26180]`
MshB `UniProtKB:P9WJN3`	catalyzes	1D-myo-inositol 2-acetamido-2-deoxy-alpha-D-glucopyranoside + H2O = 1D-myo-inositol 2-amino-2-deoxy-alpha-D-glucopyranoside + acetate `RHEA:26180`	UniProtKB:P9WJN3 Source assertion: MshB catalyzes GlcNAc-Ins deacetylation to glucosaminyl-inositol and acetate (RHEA:26180). Source location `comments[commentType=CATALYTIC ACTIVITY].reaction[RHEA:26180]`
Zn2+ `CHEBI:29105`	enables	1D-myo-inositol 2-acetamido-2-deoxy-alpha-D-glucopyranoside + H2O = 1D-myo-inositol 2-amino-2-deoxy-alpha-D-glucopyranoside + acetate `RHEA:26180`	UniProtKB:P9WJN3 Source assertion: MshB binds one zinc ion per subunit. Source location `comments[commentType=COFACTOR]; evidence PMID:12958317, PMID:16630724`
Ino1 `UniProtKB:P9WKI1`	has_cofactor UniProtKB reviewed (Swiss-Prot) annotation. UniProt evidence: ECO:0000250 (UniProtKB:Q8A7J8)	NAD(1-) `CHEBI:57540`	UniProtKB:P9WKI1 Source assertion: UniProtKB:P9WKI1 annotates CHEBI:57540 as a cofactor of this protein. Source location https://rest.uniprot.org/uniprotkb/stream?query=accession%3AP02918+OR+accession%3AP02919+OR+accession%3AP06721+OR+accession%3AP07862+OR+accession%3AP08373+OR+accession%3AP0A6B4+OR+accession%3AP0A6W3+OR+accession%3AP0A749+OR+accession%3AP0A759+OR+accession%3AP0ABG4+OR+accession%3AP0ACC7+OR+accession%3AP0AD68+OR+accession%3AP0AE16+OR+accession%3AP0AF16+OR+accession%3AP0AF18+OR+accession%3AP11880+OR+accession%3AP13016+OR+accession%3AP14900+OR+accession%3AP17169+OR+accession%3AP17443+OR+accession%3AP17952+OR+accession%3AP22188+OR+accession%3AP22634+OR+accession%3AP29012+OR+accession%3AP31120+OR+accession%3AP37773+OR+accession%3AP46022+OR+accession%3AP60932+OR+accession%3AP75949+OR+accession%3AP75959+OR+accession%3AP76008+OR+accession%3AP76535+OR+accession%3AP76577+OR+accession%3AP77272+OR+accession%3AP77570+OR+accession%3AP95189+OR+accession%3AP9WFZ5+OR+accession%3AP9WJM7+OR+accession%3AP9WJM9+OR+accession%3AP9WJN1+OR+accession%3AP9WKI1+OR+accession%3AP9WMY7+OR+accession%3AP9WN11+OR+accession%3AP9WQ19+OR+accession%3AP9WQ21+OR+accession%3AP9WQ23+OR+accession%3AQ2TL65&format=json&fields=accession%2Cprotein_name%2Cxref_sgd%2Ccc_cofactor%2Corganism_id%2Ccc_caution [sha256:f2a2d9df603885068af58d89787438192b8c396d89a4cc931ac7bbab93a74c5c] #/results/40/comments/0/cofactors/0
mca `UniProtKB:P9WJN1`	has_cofactor UniProtKB reviewed (Swiss-Prot) annotation. UniProt evidence: ECO:0000255 (HAMAP-Rule:MF_01482); ECO:0000269 (PubMed:26044118) Appears to be a Fe(2+)-dependent enzyme under physiological anaerobic conditions (PubMed:26044118). Binds Zn(2+) under aerobic conditions; this experimental artifact could become biologically relevant under oxidatively stressed conditions, such as those encountered inside activated macrophages (PubMed:14556638, PubMed:26044118). UniProt note evidence: ECO:0000269 (PubMed:14556638); ECO:0000269 (PubMed:26044118)	iron(2+) `CHEBI:29033`	UniProtKB:P9WJN1 Source assertion: UniProtKB:P9WJN1 annotates CHEBI:29033 as a cofactor of this protein. Source location https://rest.uniprot.org/uniprotkb/stream?query=accession%3AP02918+OR+accession%3AP02919+OR+accession%3AP06721+OR+accession%3AP07862+OR+accession%3AP08373+OR+accession%3AP0A6B4+OR+accession%3AP0A6W3+OR+accession%3AP0A749+OR+accession%3AP0A759+OR+accession%3AP0ABG4+OR+accession%3AP0ACC7+OR+accession%3AP0AD68+OR+accession%3AP0AE16+OR+accession%3AP0AF16+OR+accession%3AP0AF18+OR+accession%3AP11880+OR+accession%3AP13016+OR+accession%3AP14900+OR+accession%3AP17169+OR+accession%3AP17443+OR+accession%3AP17952+OR+accession%3AP22188+OR+accession%3AP22634+OR+accession%3AP29012+OR+accession%3AP31120+OR+accession%3AP37773+OR+accession%3AP46022+OR+accession%3AP60932+OR+accession%3AP75949+OR+accession%3AP75959+OR+accession%3AP76008+OR+accession%3AP76535+OR+accession%3AP76577+OR+accession%3AP77272+OR+accession%3AP77570+OR+accession%3AP95189+OR+accession%3AP9WFZ5+OR+accession%3AP9WJM7+OR+accession%3AP9WJM9+OR+accession%3AP9WJN1+OR+accession%3AP9WKI1+OR+accession%3AP9WMY7+OR+accession%3AP9WN11+OR+accession%3AP9WQ19+OR+accession%3AP9WQ21+OR+accession%3AP9WQ23+OR+accession%3AQ2TL65&format=json&fields=accession%2Cprotein_name%2Cxref_sgd%2Ccc_cofactor%2Corganism_id%2Ccc_caution [sha256:f2a2d9df603885068af58d89787438192b8c396d89a4cc931ac7bbab93a74c5c] #/results/32/comments/0/cofactors/0; /results/32/comments/0/note
MshC `UniProtKB:P9WJM9`	has_cofactor UniProtKB reviewed (Swiss-Prot) annotation. UniProt evidence: ECO:0000250 Binds 1 zinc ion per subunit. UniProt note evidence: ECO:0000250	Zn2+ `CHEBI:29105`	UniProtKB:P9WJM9 Source assertion: UniProtKB:P9WJM9 annotates CHEBI:29105 as a cofactor of this protein. Source location https://rest.uniprot.org/uniprotkb/stream?query=accession%3AP02918+OR+accession%3AP02919+OR+accession%3AP06721+OR+accession%3AP07862+OR+accession%3AP08373+OR+accession%3AP0A6B4+OR+accession%3AP0A6W3+OR+accession%3AP0A749+OR+accession%3AP0A759+OR+accession%3AP0ABG4+OR+accession%3AP0ACC7+OR+accession%3AP0AD68+OR+accession%3AP0AE16+OR+accession%3AP0AF16+OR+accession%3AP0AF18+OR+accession%3AP11880+OR+accession%3AP13016+OR+accession%3AP14900+OR+accession%3AP17169+OR+accession%3AP17443+OR+accession%3AP17952+OR+accession%3AP22188+OR+accession%3AP22634+OR+accession%3AP29012+OR+accession%3AP31120+OR+accession%3AP37773+OR+accession%3AP46022+OR+accession%3AP60932+OR+accession%3AP75949+OR+accession%3AP75959+OR+accession%3AP76008+OR+accession%3AP76535+OR+accession%3AP76577+OR+accession%3AP77272+OR+accession%3AP77570+OR+accession%3AP95189+OR+accession%3AP9WFZ5+OR+accession%3AP9WJM7+OR+accession%3AP9WJM9+OR+accession%3AP9WJN1+OR+accession%3AP9WKI1+OR+accession%3AP9WMY7+OR+accession%3AP9WN11+OR+accession%3AP9WQ19+OR+accession%3AP9WQ21+OR+accession%3AP9WQ23+OR+accession%3AQ2TL65&format=json&fields=accession%2Cprotein_name%2Cxref_sgd%2Ccc_cofactor%2Corganism_id%2Ccc_caution [sha256:f2a2d9df603885068af58d89787438192b8c396d89a4cc931ac7bbab93a74c5c] #/results/44/comments/0/cofactors/0; /results/44/comments/0/note
MshB `UniProtKB:P9WJN3`	has_cofactor UniProtKB reviewed (Swiss-Prot) annotation. UniProt evidence: ECO:0000269 (PubMed:12958317); ECO:0000269 (PubMed:16630724) Binds 1 zinc ion per subunit. UniProt note evidence: ECO:0000269 (PubMed:12958317); ECO:0000269 (PubMed:16630724)	Zn2+ `CHEBI:29105`	UniProtKB:P9WJN3 Source assertion: UniProtKB:P9WJN3 annotates CHEBI:29105 as a cofactor of this protein. Source location https://rest.uniprot.org/uniprotkb/stream?query=accession%3AH6LB59+OR+accession%3AH6LB60+OR+accession%3AH6LB61+OR+accession%3AH6LB62+OR+accession%3AH6LB64+OR+accession%3AH6LB65+OR+accession%3AH6LBE7+OR+accession%3AH6LBX4+OR+accession%3AH6LBX5+OR+accession%3AH6LBX6+OR+accession%3AH6LD21+OR+accession%3AH6LFG3+OR+accession%3AH6LFG4+OR+accession%3AH6LJY6+OR+accession%3AP9WJN3&format=json&fields=accession%2Cprotein_name%2Cxref_sgd%2Ccc_cofactor%2Corganism_id%2Ccc_caution [sha256:58c69edf7b795ede960dadfaf0093c56d2e871e90536ef0184f021222ecc1321] #/results/0/comments/0/cofactors/0; /results/0/comments/0/note

References

Reactome:R-MTU-879331 Reactome reaction R-MTU-879331
Reactome:R-MTU-879298 Reactome reaction R-MTU-879298
Reactome:R-MTU-879274 Reactome reaction R-MTU-879274
Reactome:R-MTU-879327 Reactome reaction R-MTU-879327
Reactome:R-MTU-879319 Reactome reaction R-MTU-879319
Reactome:R-MTU-879248 Reactome reaction R-MTU-879248
PMID:14763976 The Mycobacterium tuberculosis ino1 gene is essential for growth and virulence
PMID:18390549 Structural and enzymatic analysis of MshA from Corynebacterium glutamicum: substrate-assisted catalysis
PMID:20167072 Inositol monophosphate phosphatase genes of Mycobacterium tuberculosis
PMID:14556638 Characterization of Mycobacterium tuberculosis mycothiol S-conjugate amidase
PMID:12033919 ATP-dependent L-cysteine:1D-myo-inosityl 2-amino-2-deoxy-alpha-D-glucopyranoside ligase, mycothiol biosynthesis enzyme MshC, is related to class I cysteinyl-tRNA synthetases
PMID:12375100 Identification of the mycothiol synthase gene (mshD) encoding the acetyltransferase producing mycothiol in actinomycetes
Reactome:R-MTU-879299 R-MTU-879299 native structured pathway source (source version: Reactome BioPAX 97)
PMID:26044118 Identity of cofactor bound to mycothiol conjugate amidase (Mca) influenced by expression and purification conditions
UniProtKB:P9WKI1 Curated catalytic reaction RHEA:10716 for P9WKI1
UniProtKB:P9WMY7 Curated catalytic reaction RHEA:26188 for P9WMY7
UniProtKB:P9WJM9 Curated catalytic reaction RHEA:26176 for P9WJM9
UniProtKB:P9WJM7 Curated catalytic reaction RHEA:26172 for P9WJM7
UniProtKB:P9WJN3 MshB mycothiol-biosynthesis deacetylase (source version: UniProt entry retrieved 2026-10-05)
PMID:29752410 Identification and structural characterization of a histidinol phosphate phosphatase from Mycobacterium tuberculosis
UniProtKB:P9WJN1 UniProtKB P9WJN1 cofactor annotations (source version: 2026_03)

Curation history

2026-10-05T06:16:53Z Codex
- EDIT — Review complete causal graph against native sources and correct unsupported or omitted relationships
  All native sides, controllers, complexes, cofactors and cytosol locations inspected; source comments are not attributed as quotations from cited papers. Corrected Ino1/MshA stereochemical identity and MshA water/proton error; reconciled MshC/MshD charged forms/protons; added principal MshB alongside minor Mca. Removed unsupported ImpC catalyst, reidentified experimentally as HisN (PMID29752410); phosphatase catalyst remains unresolved. Every native record was inspected; see reports/causal-graph-diagram-review.json for native-object counts, exclusions and identity corrections. Semantic validation and native GraphId locator checks passed; authority snapshots and full corpus gates are coordinated separately.
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