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Information on EC 3.5.4.25 - GTP cyclohydrolase II
for references in articles please use BRENDA:EC3.5.4.25
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EC Tree 3 Hydrolases
3.5 Acting on carbon-nitrogen bonds, other than peptide bonds
3.5.4 In cyclic amidines
3.5.4.25 GTP cyclohydrolase II
IUBMB Comments
The enzyme, found in prokaryotes and some eukaryotes, hydrolytically cleaves the C-N bond at positions 8 and 9 of GTP guanine, followed by a subsequent hydrolytic attack at the base, which liberates formate, and cleavage of the α-β phosphodiester bond of the triphosphate to form diphosphate. The enzyme continues with a slow cleavage of the diphosphate to form two phosphate ions. The enzyme requires zinc and magnesium ions for the cleavage reactions at the GTP guanine and triphosphate sites, respectively. It is one of the enzymes required for flavin biosynthesis in many bacterial species, lower eukaryotes, and plants. cf. EC 3.5.4.16, GTP cyclohydrolase I, EC 3.5.4.29, GTP cyclohydrolase IIa, and EC 3.5.4.39, GTP cyclohydrolase IV.
The expected taxonomic range for this enzyme is: Bacteria, Eukaryota, Archaea
- 3.5.4.25
- riboflavin
-
anti-hcv
- lumazine
- guilliermondii
- famata
-
gtp-cyclohydrolase
-
2,5-diamino-6-ribosylamino-43h-pyrimidinone
-
flavinogenic
- 6,7-dimethyl-8-ribityllumazine
- pharmacology
- synthesis
Reaction Schemes
showSynonyms
gtp cyclohydrolase ii, riba2, 3,4-dihydroxy-2-butanone 4-phosphate synthase, gchii, gch ii, gtp cyclohydrolase 2, nbriba, gch-ii, gtpch-ii, gtp cyclohydrolase-ii, more
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SYNONYM 
ORGANISM
UNIPROT
COMMENTARY 
LITERATURE
GCH II
GCH II/III
-
enzyme variant SCO 6655 shares features of GCH II and GCH III
gch2
GCHII
GTP 7,8-8,9-dihydrolase (diphosphate-forming)
-
-
-
-
GTP-8-formylhydrolase
GTPCH2
guanosine triphosphate cyclohydrolase II
guanosine triphosphate cyclohydrolase II/3,4-dihydroxy-2-butanone-4-phosphate synthase
-
RIB1
ribA
ribA2
RIBIV
-
-
-
-
ToxB
GTP-8-formylhydrolase
-
-
-
-
guanosine triphosphate cyclohydrolase II
-
-
-
-
ribA
-
-
-
-
ribA2
bifunctional enzyme with 3,4-dihydroxy-2-butanone 4-phosphate synthase and GTP cyclohydrolase II activities
ribA2
bifunctional enzyme with 3,4-dihydroxy-2-butanone 4-phosphate synthase and GTP cyclohydrolase II activities
-
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REACTION
REACTION DIAGRAM
COMMENTARY
ORGANISM
UNIPROT
LITERATURE
GTP + 4 H2O = formate + 2,5-diamino-6-hydroxy-4-(5-phospho-D-ribosylamino)pyrimidine + 2 phosphate
GTP + 4 H2O = formate + 2,5-diamino-6-hydroxy-4-(5-phospho-D-ribosylamino)pyrimidine + 2 phosphate
-
-
-
-
GTP + 4 H2O = formate + 2,5-diamino-6-hydroxy-4-(5-phospho-D-ribosylamino)pyrimidine + 2 phosphate
2 C-N bonds are hydrolysed, releasing formate, with simultaneous removal of the terminal diphosphate, reaction mechanism
-
GTP + 4 H2O = formate + 2,5-diamino-6-hydroxy-4-(5-phospho-D-ribosylamino)pyrimidine + 2 phosphate
reaction mechanism
-
GTP + 4 H2O = formate + 2,5-diamino-6-hydroxy-4-(5-phospho-D-ribosylamino)pyrimidine + 2 phosphate
ordered reaction mechanism, in which the hydrolytic release of diphosphate preceeds the hydrolytic attack of the imidazole ring, ring opening and formate release are dependent on zinc bound to the active site, overview
-
GTP + 4 H2O = formate + 2,5-diamino-6-hydroxy-4-(5-phospho-D-ribosylamino)pyrimidine + 2 phosphate
RibA is a bifunctional enzyme possessing 3,4-dihydroxy-2-butanone 4-phosphate synthase activity, EC 4.1.99.12, located in the N-terminal half of the protein and GTP cyclohydrolase II activity of the C-terminal domain, overview
-
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REACTION TYPE
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
hydrolysis of C-N bonds
hydrolysis of phosphoesters
-
-
-
-
hydrolysis of C-N bonds
-
-
-
-
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PATHWAY SOURCE
PATHWAYS
MetaCyc
6-hydroxymethyl-dihydropterin diphosphate biosynthesis III (Chlamydia), flavin biosynthesis I (bacteria and plants), flavin biosynthesis III (fungi), toxoflavin biosynthesis
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SYSTEMATIC NAME
IUBMB Comments
GTP 7,8-8,9-dihydrolase (formate-releasing, phosphate-releasing)
The enzyme, found in prokaryotes and some eukaryotes, hydrolytically cleaves the C-N bond at positions 8 and 9 of GTP guanine, followed by a subsequent hydrolytic attack at the base, which liberates formate, and cleavage of the alpha-beta phosphodiester bond of the triphosphate to form diphosphate. The enzyme continues with a slow cleavage of the diphosphate to form two phosphate ions. The enzyme requires zinc and magnesium ions for the cleavage reactions at the GTP guanine and triphosphate sites, respectively. It is one of the enzymes required for flavin biosynthesis in many bacterial species, lower eukaryotes, and plants. cf. EC 3.5.4.16, GTP cyclohydrolase I, EC 3.5.4.29, GTP cyclohydrolase IIa, and EC 3.5.4.39, GTP cyclohydrolase IV.
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CAS REGISTRY NUMBER
COMMENTARY
56214-35-8
-
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SUBSTRATE
PRODUCT
REACTION DIAGRAM
ORGANISM
UNIPROT
LITERATURE
COMMENTARY
Reversibility
r=reversible
ir=irreversible
?=not specified
r=reversible
ir=irreversible
?=not specified
2-amino-5-formylamino-6-ribosylamino-4(3H)-pyrimidinone triphosphate + 2 H2O
formate + 2,5-diamino-6-ribosylamino-4(3H)-pyrimidinone 5'-phosphate + diphosphate
2-amino-5-formylamino-6-ribosylamino-4(3H)-pyrimidinone triphosphate + H2O
2-amino-5-formylamino-6-ribosylamino-4(3H)-pyrimidinone 5'-phosphate + diphosphate
-
Substrates: formamide-type intermediate analogue
Products: -
Products: -
?
dGTP + H2O
formate + 2,5-diamino-6-hydroxy-4-(5-phospho-deoxyribosylamino)pyrimidine + diphosphate
-
Substrates: -
Products: -
Products: -
?
GTP + 3 H2O
formate + 2,5-diamino-6-beta-ribosylamino-4(3H)-pyrimidinone 5'-phosphate + diphosphate
GTP + 3 H2O
formate + 2,5-diamino-6-hydroxy-4-(5-phospho-D-ribosylamino)pyrimidine + diphosphate
GTP + 4 H2O
formate + 2,5-diamino-6-hydroxy-4-(5-phospho-D-ribosylamino)pyrimidine + 2 phosphate
GTP + H2O
2,5-diamino-6-ribosylamino-4(3H)-pyrimidinone 5'-phosphate + diphosphate + ?
Substrates: enzyme catalyzes the first step in the biosynthesis of riboflavin
Products: -
Products: -
?
GTP + H2O
2-amino-5-formylamino-6-ribosylamino-4(3H)-pyrimidinone 5'-phosphate + diphosphate + ?
GTP + H2O
formate + 2,5-diamino-6-hydroxy-4-(5-phospho-D-ribosylamino)pyrimidine + diphosphate
GTP + H2O
formate + 2,5-diamino-6-hydroxy-4-(5-phosphoribosylamino)-pyrimidine + diphosphate
GTP + H2O
formate + 2,5-diamino-6-hydroxy-4-(5-phosphoribosylamino)pyrimidine + diphosphate
GTP + H2O
formate + 2,5-diamino-6-ribosylamino-4(3H)-pyrimidinone 5'-phosphate + diphosphate
2-amino-5-formylamino-6-ribosylamino-4(3H)-pyrimidinone 5'-triphosphate + H2O
?
-
Substrates: -
Products: -
Products: -
?
2-amino-5-formylamino-6-ribosylamino-4(3H)-pyrimidinone 5'-triphosphate + H2O
?
Substrates: -
Products: -
Products: -
?
2-amino-5-formylamino-6-ribosylamino-4(3H)-pyrimidinone triphosphate + 2 H2O
formate + 2,5-diamino-6-ribosylamino-4(3H)-pyrimidinone 5'-phosphate + diphosphate
-
Substrates: compound does serve as a substrate but not as kinetically competent intermediate
Products: -
Products: -
?
2-amino-5-formylamino-6-ribosylamino-4(3H)-pyrimidinone triphosphate + 2 H2O
formate + 2,5-diamino-6-ribosylamino-4(3H)-pyrimidinone 5'-phosphate + diphosphate
-
Substrates: formamide-type intermediate analogue
Products: -
Products: -
?
GTP + 3 H2O
formate + 2,5-diamino-6-beta-ribosylamino-4(3H)-pyrimidinone 5'-phosphate + diphosphate
-
Substrates: first committed step in the biosynthesis of riboflavin, overview
Products: -
Products: -
?
GTP + 3 H2O
formate + 2,5-diamino-6-beta-ribosylamino-4(3H)-pyrimidinone 5'-phosphate + diphosphate
-
Substrates: -
Products: spontaneous isomerization into the alpha-isomer, also the product can easily spontaneously decompose under formation of 2,4,5-triamino-4-(3H)-pyrimidone
Products: spontaneous isomerization into the alpha-isomer, also the product can easily spontaneously decompose under formation of 2,4,5-triamino-4-(3H)-pyrimidone
?
GTP + 3 H2O
formate + 2,5-diamino-6-hydroxy-4-(5-phospho-D-ribosylamino)pyrimidine + diphosphate
Substrates: -
Products: -
Products: -
?
GTP + 3 H2O
formate + 2,5-diamino-6-hydroxy-4-(5-phospho-D-ribosylamino)pyrimidine + diphosphate
Substrates: -
Products: -
Products: -
?
GTP + 4 H2O
formate + 2,5-diamino-6-hydroxy-4-(5-phospho-D-ribosylamino)pyrimidine + 2 phosphate
Substrates: -
Products: -
Products: -
?
GTP + 4 H2O
formate + 2,5-diamino-6-hydroxy-4-(5-phospho-D-ribosylamino)pyrimidine + 2 phosphate
Nakaseomyces glabratus KUE100-1
Substrates: -
Products: -
Products: -
?
GTP + 4 H2O
formate + 2,5-diamino-6-hydroxy-4-(5-phospho-D-ribosylamino)pyrimidine + 2 phosphate
Substrates: -
Products: -
Products: -
?
GTP + 4 H2O
formate + 2,5-diamino-6-hydroxy-4-(5-phospho-D-ribosylamino)pyrimidine + 2 phosphate
Substrates: -
Products: -
Products: -
?
GTP + H2O
2-amino-5-formylamino-6-ribosylamino-4(3H)-pyrimidinone 5'-phosphate + diphosphate + ?
-
Substrates: -
Products: the reaction product is exclusively formed by enzyme variant SCO 6655
Products: the reaction product is exclusively formed by enzyme variant SCO 6655
?
GTP + H2O
2-amino-5-formylamino-6-ribosylamino-4(3H)-pyrimidinone 5'-phosphate + diphosphate + ?
Substrates: -
Products: -
Products: -
?
GTP + H2O
formate + 2,5-diamino-6-hydroxy-4-(5-phospho-D-ribosylamino)pyrimidine + diphosphate
Substrates: -
Products: GMP is a second reaction product of GTP cyclohydrolase II. The ratio of the main product, 2,5-diamino-6-hydroxy-4-(5-phospho-D-ribosylamino)pyrimidine and GMP is produced at an approximate ratio of 10:1
Products: GMP is a second reaction product of GTP cyclohydrolase II. The ratio of the main product, 2,5-diamino-6-hydroxy-4-(5-phospho-D-ribosylamino)pyrimidine and GMP is produced at an approximate ratio of 10:1
?
GTP + H2O
formate + 2,5-diamino-6-hydroxy-4-(5-phospho-D-ribosylamino)pyrimidine + diphosphate
Substrates: -
Products: -
Products: -
?
GTP + H2O
formate + 2,5-diamino-6-hydroxy-4-(5-phospho-D-ribosylamino)pyrimidine + diphosphate
Substrates: -
Products: -
Products: -
?
GTP + H2O
formate + 2,5-diamino-6-hydroxy-4-(5-phosphoribosylamino)-pyrimidine + diphosphate
-
Substrates: -
Products: -
Products: -
?
GTP + H2O
formate + 2,5-diamino-6-hydroxy-4-(5-phosphoribosylamino)-pyrimidine + diphosphate
-
Substrates: -
Products: -
Products: -
?
GTP + H2O
formate + 2,5-diamino-6-hydroxy-4-(5-phosphoribosylamino)-pyrimidine + diphosphate
-
Substrates: -
Products: -
Products: -
?
GTP + H2O
formate + 2,5-diamino-6-hydroxy-4-(5-phosphoribosylamino)-pyrimidine + diphosphate
-
Substrates: -
Products: -
Products: -
?
GTP + H2O
formate + 2,5-diamino-6-hydroxy-4-(5-phosphoribosylamino)pyrimidine + diphosphate
-
Substrates: -
Products: -
Products: -
?
GTP + H2O
formate + 2,5-diamino-6-hydroxy-4-(5-phosphoribosylamino)pyrimidine + diphosphate
Substrates: -
Products: -
Products: -
?
GTP + H2O
formate + 2,5-diamino-6-hydroxy-4-(5-phosphoribosylamino)pyrimidine + diphosphate
Substrates: -
Products: -
Products: -
?
GTP + H2O
formate + 2,5-diamino-6-hydroxy-4-(5-phosphoribosylamino)pyrimidine + diphosphate
-
Substrates: first committed step in the biosynthesis of riboflavin, overview
Products: -
Products: -
?
GTP + H2O
formate + 2,5-diamino-6-hydroxy-4-(5-phosphoribosylamino)pyrimidine + diphosphate
-
Substrates: -
Products: -
Products: -
?
GTP + H2O
formate + 2,5-diamino-6-ribosylamino-4(3H)-pyrimidinone 5'-phosphate + diphosphate
-
Substrates: first committed step in the biosynthesis of riboflavin, overview
Products: -
Products: -
?
GTP + H2O
formate + 2,5-diamino-6-ribosylamino-4(3H)-pyrimidinone 5'-phosphate + diphosphate
-
Substrates: -
Products: GMP is also formed as a minor product
Products: GMP is also formed as a minor product
?
GTP + H2O
formate + 2,5-diamino-6-ribosylamino-4(3H)-pyrimidinone 5'-phosphate + diphosphate
-
Substrates: -
Products: -
Products: -
?
additional information
?
-
-
Substrates: RibA is the rate limiting enzyme in an industrial riboflavin producing strain
Products: -
Products: -
?
additional information
?
-
-
Substrates: RibA is a bifunctional enzyme possessing 3,4-dihydroxy-2-butanone 4-phosphate synthase activity, EC 4.1.99.12, located in the N-terminal half of the protein and GTP cyclohydrolase II activity of the C-terminal domain, overview
Products: -
Products: -
?
additional information
?
-
Substrates: GTP cyclohydrolase II is a slow GTPase
Products: -
Products: -
?
additional information
?
-
Substrates: substitution of Met with His leads to a protein that catalyzes the production of both 2-amino-5-formylamino-6-ribosylamino-4(3H)-pyrimidinone 5'-phosphate and 2,5-diamino-6-ribosylamino-4(3H)-pyrimidinone 5'-phosphate with equal efficiency
Products: -
Products: -
?
additional information
?
-
Substrates: substitution of Met with His leads to a protein that catalyzes the production of both 2-amino-5-formylamino-6-ribosylamino-4(3H)-pyrimidinone 5'-phosphate and 2,5-diamino-6-ribosylamino-4(3H)-pyrimidinone 5'-phosphate with equal efficiency
Products: -
Products: -
?
additional information
?
-
Substrates: substitution of Met with His leads to a protein that catalyzes the production of both 2-amino-5-formylamino-6-ribosylamino-4(3H)-pyrimidinone 5'-phosphate and 2,5-diamino-6-ribosylamino-4(3H)-pyrimidinone 5'-phosphate with equal efficiency
Products: -
Products: -
?
additional information
?
-
-
Substrates: substitution of Met with His leads to a protein that catalyzes the production of both 2-amino-5-formylamino-6-ribosylamino-4(3H)-pyrimidinone 5'-phosphate and 2,5-diamino-6-ribosylamino-4(3H)-pyrimidinone 5'-phosphate with equal efficiency
Products: -
Products: -
?
additional information
?
-
Substrates: enzyme may be involved in the biosynthesis of toxoflavin, which is produced from GTP in a series of steps that are likely initiated by GCH II
Products: -
Products: -
?
additional information
?
-
Substrates: enzyme may be involved in the biosynthesis of toxoflavin, which is produced from GTP in a series of steps that are likely initiated by GCH II
Products: -
Products: -
?
additional information
?
-
Substrates: enzyme may be involved in the biosynthesis of toxoflavin, which is produced from GTP in a series of steps that are likely initiated by GCH II
Products: -
Products: -
?
additional information
?
-
-
Substrates: enzyme may be involved in the biosynthesis of toxoflavin, which is produced from GTP in a series of steps that are likely initiated by GCH II
Products: -
Products: -
?
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NATURAL SUBSTRATE
NATURAL PRODUCT
REACTION DIAGRAM
ORGANISM
UNIPROT
LITERATURE
COMMENTARY
REVERSIBILITY
r=reversible
ir=irreversible
?=not specified
r=reversible
ir=irreversible
?=not specified
GTP + 3 H2O
formate + 2,5-diamino-6-beta-ribosylamino-4(3H)-pyrimidinone 5'-phosphate + diphosphate
-
Substrates: first committed step in the biosynthesis of riboflavin, overview
Products: -
Products: -
?
GTP + 3 H2O
formate + 2,5-diamino-6-hydroxy-4-(5-phospho-D-ribosylamino)pyrimidine + diphosphate
GTP + 4 H2O
formate + 2,5-diamino-6-hydroxy-4-(5-phospho-D-ribosylamino)pyrimidine + 2 phosphate
GTP + H2O
2,5-diamino-6-ribosylamino-4(3H)-pyrimidinone 5'-phosphate + diphosphate + ?
Substrates: enzyme catalyzes the first step in the biosynthesis of riboflavin
Products: -
Products: -
?
GTP + H2O
2-amino-5-formylamino-6-ribosylamino-4(3H)-pyrimidinone 5'-phosphate + diphosphate + ?
Substrates: -
Products: -
Products: -
?
GTP + H2O
formate + 2,5-diamino-6-hydroxy-4-(5-phospho-D-ribosylamino)pyrimidine + diphosphate
GTP + H2O
formate + 2,5-diamino-6-hydroxy-4-(5-phosphoribosylamino)-pyrimidine + diphosphate
GTP + H2O
formate + 2,5-diamino-6-hydroxy-4-(5-phosphoribosylamino)pyrimidine + diphosphate
GTP + H2O
formate + 2,5-diamino-6-ribosylamino-4(3H)-pyrimidinone 5'-phosphate + diphosphate
-
Substrates: first committed step in the biosynthesis of riboflavin, overview
Products: -
Products: -
?
GTP + 3 H2O
formate + 2,5-diamino-6-hydroxy-4-(5-phospho-D-ribosylamino)pyrimidine + diphosphate
Substrates: -
Products: -
Products: -
?
GTP + 3 H2O
formate + 2,5-diamino-6-hydroxy-4-(5-phospho-D-ribosylamino)pyrimidine + diphosphate
Substrates: -
Products: -
Products: -
?
GTP + 4 H2O
formate + 2,5-diamino-6-hydroxy-4-(5-phospho-D-ribosylamino)pyrimidine + 2 phosphate
Substrates: -
Products: -
Products: -
?
GTP + 4 H2O
formate + 2,5-diamino-6-hydroxy-4-(5-phospho-D-ribosylamino)pyrimidine + 2 phosphate
Nakaseomyces glabratus KUE100-1
Substrates: -
Products: -
Products: -
?
GTP + 4 H2O
formate + 2,5-diamino-6-hydroxy-4-(5-phospho-D-ribosylamino)pyrimidine + 2 phosphate
Substrates: -
Products: -
Products: -
?
GTP + 4 H2O
formate + 2,5-diamino-6-hydroxy-4-(5-phospho-D-ribosylamino)pyrimidine + 2 phosphate
Substrates: -
Products: -
Products: -
?
GTP + H2O
formate + 2,5-diamino-6-hydroxy-4-(5-phospho-D-ribosylamino)pyrimidine + diphosphate
Substrates: -
Products: GMP is a second reaction product of GTP cyclohydrolase II. The ratio of the main product, 2,5-diamino-6-hydroxy-4-(5-phospho-D-ribosylamino)pyrimidine and GMP is produced at an approximate ratio of 10:1
Products: GMP is a second reaction product of GTP cyclohydrolase II. The ratio of the main product, 2,5-diamino-6-hydroxy-4-(5-phospho-D-ribosylamino)pyrimidine and GMP is produced at an approximate ratio of 10:1
?
GTP + H2O
formate + 2,5-diamino-6-hydroxy-4-(5-phospho-D-ribosylamino)pyrimidine + diphosphate
Substrates: -
Products: -
Products: -
?
GTP + H2O
formate + 2,5-diamino-6-hydroxy-4-(5-phospho-D-ribosylamino)pyrimidine + diphosphate
Substrates: -
Products: -
Products: -
?
GTP + H2O
formate + 2,5-diamino-6-hydroxy-4-(5-phosphoribosylamino)-pyrimidine + diphosphate
-
Substrates: -
Products: -
Products: -
?
GTP + H2O
formate + 2,5-diamino-6-hydroxy-4-(5-phosphoribosylamino)-pyrimidine + diphosphate
-
Substrates: -
Products: -
Products: -
?
GTP + H2O
formate + 2,5-diamino-6-hydroxy-4-(5-phosphoribosylamino)-pyrimidine + diphosphate
-
Substrates: -
Products: -
Products: -
?
GTP + H2O
formate + 2,5-diamino-6-hydroxy-4-(5-phosphoribosylamino)-pyrimidine + diphosphate
-
Substrates: -
Products: -
Products: -
?
GTP + H2O
formate + 2,5-diamino-6-hydroxy-4-(5-phosphoribosylamino)pyrimidine + diphosphate
-
Substrates: -
Products: -
Products: -
?
GTP + H2O
formate + 2,5-diamino-6-hydroxy-4-(5-phosphoribosylamino)pyrimidine + diphosphate
-
Substrates: first committed step in the biosynthesis of riboflavin, overview
Products: -
Products: -
?
additional information
?
-
-
Substrates: RibA is the rate limiting enzyme in an industrial riboflavin producing strain
Products: -
Products: -
?
additional information
?
-
Substrates: GTP cyclohydrolase II is a slow GTPase
Products: -
Products: -
?
additional information
?
-
Substrates: substitution of Met with His leads to a protein that catalyzes the production of both 2-amino-5-formylamino-6-ribosylamino-4(3H)-pyrimidinone 5'-phosphate and 2,5-diamino-6-ribosylamino-4(3H)-pyrimidinone 5'-phosphate with equal efficiency
Products: -
Products: -
?
additional information
?
-
Substrates: substitution of Met with His leads to a protein that catalyzes the production of both 2-amino-5-formylamino-6-ribosylamino-4(3H)-pyrimidinone 5'-phosphate and 2,5-diamino-6-ribosylamino-4(3H)-pyrimidinone 5'-phosphate with equal efficiency
Products: -
Products: -
?
additional information
?
-
Substrates: substitution of Met with His leads to a protein that catalyzes the production of both 2-amino-5-formylamino-6-ribosylamino-4(3H)-pyrimidinone 5'-phosphate and 2,5-diamino-6-ribosylamino-4(3H)-pyrimidinone 5'-phosphate with equal efficiency
Products: -
Products: -
?
additional information
?
-
-
Substrates: substitution of Met with His leads to a protein that catalyzes the production of both 2-amino-5-formylamino-6-ribosylamino-4(3H)-pyrimidinone 5'-phosphate and 2,5-diamino-6-ribosylamino-4(3H)-pyrimidinone 5'-phosphate with equal efficiency
Products: -
Products: -
?
additional information
?
-
Substrates: enzyme may be involved in the biosynthesis of toxoflavin, which is produced from GTP in a series of steps that are likely initiated by GCH II
Products: -
Products: -
?
additional information
?
-
Substrates: enzyme may be involved in the biosynthesis of toxoflavin, which is produced from GTP in a series of steps that are likely initiated by GCH II
Products: -
Products: -
?
additional information
?
-
Substrates: enzyme may be involved in the biosynthesis of toxoflavin, which is produced from GTP in a series of steps that are likely initiated by GCH II
Products: -
Products: -
?
additional information
?
-
-
Substrates: enzyme may be involved in the biosynthesis of toxoflavin, which is produced from GTP in a series of steps that are likely initiated by GCH II
Products: -
Products: -
?
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METALS and IONS
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
Mg2+
Zn2+
Zn2+
-
wild-type enzyme contains 0.71 mol Zn2+ per mol of subunit, while the content in the mutant enzymes is reduced to below 0.1 mol Zn2+ per mol of subunit, essential for activity, bound to the active site, required for ring opening and formate release with zinc acting as a Lewis acid, which activates the 2 water molecules involved in the sequential hydrolysis of 2 carbon-nitrogen bonds
Zn2+
content 1 molecule per monomer enzyme, enzyme requires a zinc ion which presumably activates a water molecule for excision of C-8 of GTP
Zn2+
content of 1 molecule per enzyme monomer, enzyme requires a zinc ion which presumably activates a water molecule for excision of C-8 of GTP
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INHIBITOR
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
IMAGE
phosphate
-
partial uncompetitive at low concentration, competitive at concentrations above 6 mM
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DISEASE
TITLE OF PUBLICATION
LINK TO PUBMED
Tuberculosis
Structural basis for pH dependent monomer-dimer transition of 3,4-dihydroxy 2-butanone-4-phosphate synthase domain from Mycobacterium tuberculosis.
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KM VALUE [mM]
SUBSTRATE
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
IMAGE
0.031
2-amino-5-formylamino-6-ribosylamino-4(3H)-pyrimidinone 5'-triphosphate
-
wild type enzyme, at pH 8.5 and 30°C
0.079
2-amino-5-formylamino-6-ribosylamino-4(3H)-pyrimidinone 5'-triphosphate
-
mutant enzyme Y210C/A290T/Q293R/A296T/K322R/M361I, at pH 8.5 and 30°C
0.122
2-amino-5-formylamino-6-ribosylamino-4(3H)-pyrimidinone 5'-triphosphate
-
mutant enzyme Y210C/A290T/Q293R/A296T/K322R/F339Y/M361I, at pH 8.5 and 30°C
0.008
GTP
variant M120Y, 1 mM substrate, 0.1 M Tris-HCl, pH 8, 5 mM MgCl2, 0.5 mM dithiothreitol
0.008
GTP
M120Y variant, 1 mM substrate, 0.1 M Tris-HCl, pH 8, 5 mM MgCl2, 0.5 mM dithiothreitol
0.0089
GTP
M120K variant, 1 mM substrate, 0.1 M Tris-HCl, pH 8, 5 mM MgCl2, 0.5 mM dithiothreitol
0.011
GTP
M120Q variant, 1 mM substrate, 0.1 M Tris-HCl, pH 8, 5 mM MgCl2, 0.5 mM dithiothreitol
0.015
GTP
M120I variant, 1 mM substrate, 0.1 M Tris-HCl, pH 8, 5 mM MgCl2, 0.5 mM dithiothreitol
0.019
GTP
variant M120F, 1 mM substrate, 0.1 M Tris-HCl, pH 8, 5 mM MgCl2, 0.5 mM dithiothreitol
0.019
GTP
M120F variant, 1 mM substrate, 0.1 M Tris-HCl, pH 8, 5 mM MgCl2, 0.5 mM dithiothreitol
0.024
GTP
wild type, 1 mM substrate, 0.1 M Tris-HCl, pH 8, 5 mM MgCl2, 0.5 mM dithiothreitol
0.033
GTP
M120S variant, 1 mM substrate, 0.1 M Tris-HCl, pH 8, 5 mM MgCl2, 0.5 mM dithiothreitol
0.044
GTP
-
mutant enzyme Y210C/A290T/Q293R/A296T/K322R/F339Y/M361I, at pH 8.5 and 30°C
0.048
GTP
variant Y123M, 1 mM substrate, 0.1 M Tris-HCl, pH 8, 5 mM MgCl2, 0.5 mM dithiothreitol
0.049
GTP
-
mutant enzyme Y210C/A290T/Q293R/A296T/K322R/M361I, at pH 8.5 and 30°C
0.05
GTP
M120H variant, 1 mM substrate, 0.1 M Tris-HCl, pH 8, 5 mM MgCl2, 0.5 mM dithiothreitol
0.056
GTP
wild type, 1 mM substrate, 0.1 M Tris-HCl, pH 8, 5 mM MgCl2, 0.5 mM dithiothreitol
0.059
GTP
M120A variant, 1 mM substrate, 0.1 M Tris-HCl, pH 8, 5 mM MgCl2, 0.5 mM dithiothreitol
0.063
GTP
wild type, 1 mM substrate, 0.1 M Tris-HCl, pH 8, 5 mM MgCl2, 0.5 mM dithiothreitol
0.067
GTP
M120N variant, 1 mM substrate, 0.1 M Tris-HCl, pH 8, 5 mM MgCl2, 0.5 mM dithiothreitol
0.067
GTP
M120C variant, 1 mM substrate, 0.1 M Tris-HCl, pH 8, 5 mM MgCl2, 0.5 mM dithiothreitol
0.085
GTP
variant D127A, 1 mM substrate, 0.1 M Tris-HCl, pH 8, 5 mM MgCl2, 0.5 mM dithiothreitol
0.092
GTP
variant R123M, 1 mM substrate, 0.1 M Tris-HCl, pH 8, 5 mM MgCl2, 0.5 mM dithiothreitol
0.1267
GTP
full-length bifunctional enzyme ribA2, at pH 8.0 and 37°C
0.15
GTP
M120T variant, 1 mM substrate, 0.1 M Tris-HCl, pH 8, 5 mM MgCl2, 0.5 mM dithiothreitol
0.1505
GTP
GCHII-domain of enzyme ribA2, at pH 8.0 and 37°C
0.19
GTP
M120G variant, 1 mM substrate, 0.1 M Tris-HCl, pH 8, 5 mM MgCl2, 0.5 mM dithiothreitol
0.23
GTP
variant G209D, 1 mM substrate, 0.1 M Tris-HCl, pH 8, 5 mM MgCl2, 0.5 mM dithiothreitol
additional information
additional information
-
kinetics, cooperative reaction with a Hill coefficient of 1.3
-
additional information
additional information
-
pre-steady state kinetics, single turnover experiments, stopped-flow experiments
-
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TURNOVER NUMBER [1/s]
SUBSTRATE
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
IMAGE
0.05
2-amino-5-formylamino-6-ribosylamino-4(3H)-pyrimidinone 5'-triphosphate
-
wild type enzyme, at pH 8.5 and 30°C
0.09
2-amino-5-formylamino-6-ribosylamino-4(3H)-pyrimidinone 5'-triphosphate
-
mutant enzyme Y210C/A290T/Q293R/A296T/K322R/M361I, at pH 8.5 and 30°C
0.1
2-amino-5-formylamino-6-ribosylamino-4(3H)-pyrimidinone 5'-triphosphate
-
mutant enzyme Y210C/A290T/Q293R/A296T/K322R/F339Y/M361I, at pH 8.5 and 30°C
0.0033
GTP
full-length bifunctional enzyme ribA2, at pH 8.0 and 37°C
0.065
GTP
-
mutant enzyme Y210C/A290T/Q293R/A296T/K322R/M361I, at pH 8.5 and 30°C
0.072
GTP
-
mutant enzyme Y210C/A290T/Q293R/A296T/K322R/F339Y/M361I, at pH 8.5 and 30°C
0.42
GTP
M120D variant, 1 mM substrate, 0.1 M Tris-HCl, pH 8, 5 mM MgCl2, 0.5 mM dithiothreitol
1.2
GTP
variant Y326F, 1 mM substrate, 0.1 M Tris-HCl, pH 8, 5 mM MgCl2, 0.5 mM dithiothreitol
1.8
GTP
M120W variant, 1 mM substrate, 0.1 M Tris-HCl, pH 8, 5 mM MgCl2, 0.5 mM dithiothreitol
3.18
GTP
M120E variant, 1 mM substrate, 0.1 M Tris-HCl, pH 8, 5 mM MgCl2, 0.5 mM dithiothreitol
3.18
GTP
SCO 2687, variant Y123F, 1 mM substrate, 0.1 M Tris-HCl, pH 8, 5 mM MgCl2, 0.5 mM dithiothreitol
4.86
GTP
variant Y326M, 1 mM substrate, 0.1 M Tris-HCl, pH 8, 5 mM MgCl2, 0.5 mM dithiothreitol
10.8
GTP
M120H variant, 1 mM substrate, 0.1 M Tris-HCl, pH 8, 5 mM MgCl2, 0.5 mM dithiothreitol
20.4
GTP
M120T variant, 1 mM substrate, 0.1 M Tris-HCl, pH 8, 5 mM MgCl2, 0.5 mM dithiothreitol
42
GTP
M120A variant, 1 mM substrate, 0.1 M Tris-HCl, pH 8, 5 mM MgCl2, 0.5 mM dithiothreitol
46.8
GTP
variant M120F, 1 mM substrate, 0.1 M Tris-HCl, pH 8, 5 mM MgCl2, 0.5 mM dithiothreitol
57
GTP
M120G variant, 1 mM substrate, 0.1 M Tris-HCl, pH 8, 5 mM MgCl2, 0.5 mM dithiothreitol
66
GTP
M120C variant, 1 mM substrate, 0.1 M Tris-HCl, pH 8, 5 mM MgCl2, 0.5 mM dithiothreitol
78
GTP
M120I variant, 1 mM substrate, 0.1 M Tris-HCl, pH 8, 5 mM MgCl2, 0.5 mM dithiothreitol
78
GTP
SCO 2687, variant D127A, 1 mM substrate, 0.1 M Tris-HCl, pH 8, 5 mM MgCl2, 0.5 mM dithiothreitol
84
GTP
variant M120Y, 1 mM substrate, 0.1 M Tris-HCl, pH 8, 5 mM MgCl2, 0.5 mM dithiothreitol
84
GTP
M120S variant, 1 mM substrate, 0.1 M Tris-HCl, pH 8, 5 mM MgCl2, 0.5 mM dithiothreitol
108
GTP
M120N variant, 1 mM substrate, 0.1 M Tris-HCl, pH 8, 5 mM MgCl2, 0.5 mM dithiothreitol
120
GTP
M120Q variant, 1 mM substrate, 0.1 M Tris-HCl, pH 8, 5 mM MgCl2, 0.5 mM dithiothreitol
150
GTP
wild type, 1 mM substrate, 0.1 M Tris-HCl, pH 8, 5 mM MgCl2, 0.5 mM dithiothreitol
168
GTP
SCO 2687, variant G209D, 1 mM substrate, 0.1 M Tris-HCl, pH 8, 5 mM MgCl2, 0.5 mM dithiothreitol
204
GTP
SCO 2687, wild type, 1 mM substrate, 0.1 M Tris-HCl, pH 8, 5 mM MgCl2, 0.5 mM dithiothreitol
228
GTP
SCO 2687, variant R123M, 1 mM substrate, 0.1 M Tris-HCl, pH 8, 5 mM MgCl2, 0.5 mM dithiothreitol
348
GTP
SCO 2687, variant Y123M, 1 mM substrate, 0.1 M Tris-HCl, pH 8, 5 mM MgCl2, 0.5 mM dithiothreitol
432
GTP
wild type, 1 mM substrate, 0.1 M Tris-HCl, pH 8, 5 mM MgCl2, 0.5 mM dithiothreitol
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kcat/KM VALUE [1/mMs-1]
SUBSTRATE
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
IMAGE
1.4
GTP
full-length bifunctional enzyme ribA2, at pH 8.0 and 37°C
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Ki VALUE [mM]
INHIBITOR
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
IMAGE
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SPECIFIC ACTIVITY [µmol/min/mg]
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
0.015
-
purified recombinant wild-type enzyme, substrate 2-amino-5-formylamino-6-ribosylamino-4(3H)-pyrimidinone triphosphate cleaved to 2-amino-5-formylamino-6-ribosylamino-4(3H)-pyrimidinone 5'-phosphate
0.025
-
purified recombinant wild-type enzyme, substrate dGTP cleaved to dGMP
0.038
-
purified recombinant wild-type enzyme, substrate dGTP cleaved to 2,5-diamino-6-hydroxy-4-(5-phospho-deoxyribosylamino)pyrimidine
0.122
-
purified recombinant wild-type enzyme, substrate 2-amino-5-formylamino-6-ribosylamino-4(3H)-pyrimidinone triphosphate cleaved to 2,5-diamino-6-hydroxy-4-(5-phosphoribosylamino)pyrimidine
0.182
-
purified recombinant wild-type enzyme, substrate GTP cleaved to 2,5-diamino-6-hydroxy-4-(5-phosphoribosylamino)pyrimidine
additional information
-
activity of the mutant enzyme C54S, C65S, and C67S with the different substrates, overview, best substrate is GTP being cleaved to GMP
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pH OPTIMUM
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
8.5
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pH RANGE
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
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TEMPERATURE OPTIMUM
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
37
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pI VALUE
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
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ORGANISM
COMMENTARY
LITERATURE
UNIPROT
SEQUENCE DB
SOURCE
guanosine triphosphate cyclohydrolase II/3,4-dihydroxy-2-butanone-4-phosphate synthase; gene NbRibA encoding the bifunctional guanosine triphosphate cyclohydrolase II/3,4-dihydroxy-2-butanone-4-phosphate synthase
UniProt
brenda
single gene ribA2 or Rv1415, encodes for the bifunctional enzyme with DHBPS and GTPCH-II domains
-
-
brenda
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SOURCE TISSUE
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
SOURCE
Highest Expressing Human Cell Lines
Cell Line LinksPlease wait a moment until the data is sorted. This message will disappear when the data is sorted.
GENERAL INFORMATION
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
drug target
malfunction
metabolism
physiological function
additional information
-
bifunctional enzyme with 3,4-dihydroxy 2-butanone 4-phosphate synthase, DHBPS EC 4.1.99.12, and GTP cyclohydrolase-II, GTPCH-II, domains at N- and C-termini, respectively
drug target
Candida glabrata is an opportunistic pathogen causing candidiasis especially in patients with immunocompromised state. The GCH2-dependent nitrosative stress detoxifying mechanism is a promising target for the development of novel antifungals
drug target
Nakaseomyces glabratus KUE100-1
-
Candida glabrata is an opportunistic pathogen causing candidiasis especially in patients with immunocompromised state. The GCH2-dependent nitrosative stress detoxifying mechanism is a promising target for the development of novel antifungals
-
malfunction
NbRibA-silenced plants show slightly dwarf phenotypes, levels of endogenous riboflavin and its derivatives FMN and FAD are decreased in NbRibA-silenced Nicotiana benthamiana plants. Silencing of NbRibA compromises not only hypersensitive response cell death, but also the NO and reactive oxygen species production induced by INF1 elicitin and a constitutively active form of NbMEK2, and also induces high susceptibility to oomycete Phytophthora infestans and ascomycete Colletotrichum orbiculare. Compromised radical production and hypersensitive response cell death induced by INF1 in NbRibA-silenced leaves are rescued by adding riboflavin, FMN or FAD
metabolism
-
GTP cyclohydrolase II catalyzes the first dedicated step in the biosynthesis of riboflavin
metabolism
GCH II catalyzes the first committed step in the riboflavin biosynthetic pathway
metabolism
-
3,4-dihydroxy 2-butanone 4-phosphate synthase, DHBPS EC 4.1.99.12, and GTP cyclohydrolase-II, GTPCH-II, are the two initial enzymes involved in riboflavin biosynthesis pathway, which is essential for the pathogen
metabolism
the bifunctional enzyme, guanosine triphosphate cyclohydrolase II/3,4-dihydroxy-2-butanone-4-phosphate synthase, participates in the biosynthesis of flavin
metabolism
GTP cyclohydrolase II catalyzes the first committed step in the biosynthesis of riboflavin
metabolism
the enzyme is essential for pathogens. The enzyme can regulate its catalytic activity depending on the redox environment
metabolism
the enzyme is involved in riboflavin biosynthesis and in biosynthesis of toxoflavin (a phytotoxin that contributes the virulence of this phytopathogen)
metabolism
the enzyme catalyzes the first step in riboflavin biosynthesis
metabolism
-
GCH II catalyzes the first committed step in the riboflavin biosynthetic pathway
-
metabolism
-
the enzyme is involved in riboflavin biosynthesis and in biosynthesis of toxoflavin (a phytotoxin that contributes the virulence of this phytopathogen)
-
metabolism
-
the enzyme catalyzes the first step in riboflavin biosynthesis
-
metabolism
-
the enzyme is essential for pathogens. The enzyme can regulate its catalytic activity depending on the redox environment
-
physiological function
-
3,4-dihydroxy 2-butanone 4-phosphate synthase, DHBPS EC 4.1.99.12, and GTP cyclohydrolase-II, GTPCH-II, are the two initial enzymes involved in riboflavin biosynthesis pathway, which is essential for the pathogen
physiological function
the enzyme confers nitrosative stress resistance on yeast cells. The proliferation of Candida glabrata in cultures of macrophage-like cells required the GCH2-dependent nitrosative stress detoxifying mechanism
physiological function
GTPCH2 enzymatic activity of Rib1 is essential for RIB1-dependent nitrosative stress tolerance
physiological function
-
GTPCH2 enzymatic activity of Rib1 is essential for RIB1-dependent nitrosative stress tolerance
-
physiological function
Nakaseomyces glabratus KUE100-1
-
the enzyme confers nitrosative stress resistance on yeast cells. The proliferation of Candida glabrata in cultures of macrophage-like cells required the GCH2-dependent nitrosative stress detoxifying mechanism
-
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PDB
SCOP
CATH
UNIPROT
ORGANISM
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MOLECULAR WEIGHT
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
44000
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SUBUNIT
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
homodimer
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CRYSTALLIZATION (Commentary)
ORGANISM
UNIPROT
LITERATURE
the enzyme is crystallized in oxidized form, the expulsion of Zn(2+) upon oxidation of catalytic cysteines reveales its ability to act in response to the redox environment. The crystal structure of Helicobacter pylori, unlike other GCHII structures, reveales that cysteines at the active site exist in oxidized state forming two disulfide bonds
sitting drop vapor diffusion method, using 0.1 M Na HEPES pH 7.5, 15% (w/v) PEG 8000
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PROTEIN VARIANTS
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
Y210C/A290T/Q293R/A296T/K322R/F339Y/M361I
-
the mutant shows a 2fold increase in GTP cyclohydrolase II activity and a 4fold increase in the Km value with GTP as the substrate. Using 2-amino-5-formylamino-6-ribosylamino-4(3H)-pyrimidinone 5'-triphosphate as the substrate, the mutant shows a rate enhancement by a factor of about 2 and an increase in the Km value by a factor of about 5
Y210C/A290T/Q293R/A296T/K322R/M361I
-
the mutant shows increased kcat and Km values compared to the wild type enzyme using GTP and 2-amino-5-formylamino-6-ribosylamino-4(3H)-pyrimidinone 5'-triphosphate as the substrate
C54S
-
site-directed mutagenesis, mutation results in proteins devoid of bound zinc and unable to release formate from the imidazole ring of GTP or from the intermediate analogue 2-amino-5-formylamino-6-ribosylamino-4(3H)-pyrimidinone 5'-triphosphate, however, the mutant enzyme is still capable to release diphosphate from GTP and from the formamide-type intermediate analogue
C65S
-
site-directed mutagenesis, mutation results in proteins devoid of bound zinc and unable to release formate from the imidazole ring of GTP or from the intermediate analogue 2-amino-5-formylamino-6-ribosylamino-4(3H)-pyrimidinone 5'-triphosphate, however, the mutant enzyme is still capable to release diphosphate from GTP and from the formamide-type intermediate analogue
C67S
-
site-directed mutagenesis, mutation results in proteins devoid of bound zinc and unable to release formate from the imidazole ring of GTP or from the intermediate analogue 2-amino-5-formylamino-6-ribosylamino-4(3H)-pyrimidinone 5'-triphosphate, however, the mutant enzyme is still capable to release diphosphate from GTP and from the formamide-type intermediate analogue
D127A
about 10fold less efficient than the wild-type protein
G209D
about 10fold less efficient than the wild-type protein
R83H
mutant substantially impaired in overall activity
Y123M
about 10fold less efficient than the wild-type protein, produces exclusively 2-amino-5-formylamino-6-ribosylamino-4(3H)-pyrimidinone 5'-phosphate
Y326F
generated by site-directed mutagenesis, catalytically inactive variant
Y326M
generated by site-directed mutagenesis, catalytically inactive variant
additional information
additional information
-
an additional single copy of the ribA gene introduced into the sacBlocus of the riboflavin production strain and constitutive expression from the medium strength vegI promoter leads to improved riboflavin titers and yields of riboflavin on glucose of up to 25%, strain VB2XL1, both enzymatic activities of RibA, the 3,4-dihydroxy-2-butanone 4-phosphate synthase activity located in the N-terminal half of the protein and the GTP cyclohydrolase II activity of the C-terminal domain, are necessary for the improved riboflavin productivity, method, overview
additional information
generation of NbRibA-silenced plants via inoculation with Agrobacterium tumefaciens containing inf1, NbMEK2DD or Bax, or GUS as a control. Silencing NbRibA does not affect the activation of SIPK and defense-related genes, except for NbGST, effects of silencing NbRibA on disease resistance, phenotype
additional information
-
generation of NbRibA-silenced plants via inoculation with Agrobacterium tumefaciens containing inf1, NbMEK2DD or Bax, or GUS as a control. Silencing NbRibA does not affect the activation of SIPK and defense-related genes, except for NbGST, effects of silencing NbRibA on disease resistance, phenotype
additional information
-
the M120T variant of GCH II/II SCO 6655 acquires the ability to catalyze the conversion of GTP to 2,5-diamino-6-ribosylamino-4(3H)-pyrimidinone 5'-phosphate
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TEMPERATURE STABILITY
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
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STORAGE STABILITY
ORGANISM
UNIPROT
LITERATURE
-20°C, 1 mg/ml, pH8, in presence of EDTA and an excess of Mg2+, quite stable
-
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PURIFICATION (Commentary)
ORGANISM
UNIPROT
LITERATURE
ammonium sulfate precipitation, Ni-NTA column chromatography, and Sephacryl S-200 gel filtration
DEAE-Sephadex column chromatography, Q-Sepharose column chromatography, butyl-Sepharose column chromatography, and Sephacryl S-300 gel filtration
-
purification of wild type enzyme and its mutants by nickel affinity chromatography, site-directed variants are expressed in the native state and purified to homogeneity by ion exchange and hydrophobic interaction chromatographic steps
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CLONED (Commentary)
ORGANISM
UNIPROT
LITERATURE
expressed in Escherichia coli BL21(DE3) cells
expression in Escherichia coli
gene ribA2, DNA and amino acid sequence analysis and comparison of DHBPS/GTPCH-II sequences
-
overexpression and purification of wild type and site-directed variants of GCH II
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APPLICATION
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
pharmacology
-
enzyme is a potential drug target, since numerous pathogenic microorganims are absolutely dependent on endogenous synthesis of riboflavin, target for development of bactericidal inhibitors
synthesis
-
the enzyme is essential for industrial riboflavin production by Bacillus subtilis overproducing strains, overview
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REF.
AUTHORS
TITLE
JOURNAL
VOL.
PAGES
YEAR
ORGANISM (UNIPROT)
PUBMED ID
SOURCE
Blau, N.; Niederwieser, A.
GTP-cyclohydrolases: a review
J. Clin. Chem. Clin. Biochem.
23
169-176
1985
Escherichia coli, Meyerozyma guilliermondii
brenda
Foor, F.; Brown, G.M.
GTP cyclohydrolase II from Escherichia coli
Methods Enzymol.
66
303-307
1980
Escherichia coli
brenda
Foor, F.; Brown, G.M.
Purification and properties of guanosine triphosphate cyclohydrolase II from Escherichia coli
J. Biol. Chem.
250
3545-3551
1975
Escherichia coli
brenda
Herz, S.; Eberhardt, S.; Bacher, A.
Biosynthesis of riboflavin in plants. The rib A gene of Arabidopsis thaliana specifies a bifunctional GTP cyclohydrolase II/3,4-dihydroxy-2-butanone 4-phosphate synthase
Phytochemistry
53
723-731
2000
Arabidopsis thaliana
brenda
Bacher, A.; Richter, G.; Ritz, H.; Eberhardt, S.; Fischer, M.; Krieger, C.
Biosynthesis of riboflavin: GTP-cyclohydrolase II, deaminase, and reductase
Methods Enzymol.
280
382-389
1997
Escherichia coli
brenda
Bereswill, S.; Fassbinder, F.; Vlzing, C.; Covacci, A.; Haas, R.; Kist, M.
Hemolytic properties and riboflavin synthesis of Helicobacter pylori: cloning and functional characterization of the ribA gene encoding GTP-cyclohydrolase II that confers hemolytic activity to Escherichia coli
Med. Microbiol. Immunol.
186
177-187
1998
Helicobacter pylori
brenda
Kobayashi, M.; Ohara-Nemoto, Y.; Kaneko, M.; Hayakawa, H.; Sekiguchi, M.; Yamamoto, K.
Potential of Escherichia coli GTP cyclohydrolase II for hydrolyzing 8-oxo-dGTP, a mutagenic substrate for DNA synthesis
J. Biol. Chem.
273
26394-26399
1988
Escherichia coli
brenda
Kaiser, J.; Schramek, N.; Eberhardt, S.; Puttmer, S.; Schuster, M.; Bacher, A.
Biosynthesis of vitamin B2. An essential zinc ion at the catalytic site of GTP cyclohydrolase II
Eur. J. Biochem.
269
5264-5270
2002
Escherichia coli
brenda
Ritz, H.; Schramek, N.; Bracher, A.; Herz, S.; Eisenreich, W.; Richter, G.; Bacher, A.
Biosynthesis of riboflavin: studies on the mechanism of GTP cyclohydrolase II
J. Biol. Chem.
276
22273-22277
2001
Escherichia coli
brenda
Schramek, N.; Bracher, A.; Bacher, A.
Biosynthesis of riboflavin. Single turnover kinetic analysis of GTP cyclohydrolase II
J. Biol. Chem.
276
44157-44162
2001
Escherichia coli
brenda
Ren, J.; Kotaka, M.; Lockyer, M.; Lamb, H.K.; Hawkins, A.R.; Stammers, D.K.
GTP cyclohydrolase II structure and mechanism
J. Biol. Chem.
280
36912-36919
2005
Escherichia coli
brenda
Huembelin, M.; Griesser, V.; Keller, T.; Schurter, W.; Haiker, M.; Hohmann, H.P.; Ritz, H.; Richter, G.; Bacher, A.; Van Loon, A.P.G.M.
GTP cyclohydrolase II and 3,4-dihydroxy-2-butanone 4-phosphate synthase are rate-limiting enzymes in riboflavin synthesis of an industrial Bacillus subtilis strain used for riboflavin production
J. Indust. Microbiol. Biotechnol.
22
1-7
1999
Bacillus subtilis
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brenda
Spoonamore, J.E.; Dahlgran, A.L.; Jacobsen, N.E.; Bandarian, V.
Evolution of new function in the GTP cyclohydrolase II proteins of Streptomyces coelicolor
Biochemistry
45
12144-12155
2006
Streptomyces coelicolor
brenda
Spoonamore, J.E.; Bandarian, V.
Understanding functional divergence in proteins by studying intragenomic homologues
Biochemistry
47
2592-2600
2008
Streptomyces coelicolor (O88011), Streptomyces coelicolor (Q9EWJ8), Streptomyces coelicolor (Q9KYI5), Streptomyces coelicolor
brenda
Lehmann, M.; Degen, S.; Hohmann, H.P.; Wyss, M.; Bacher, A.; Schramek, N.
Biosynthesis of riboflavin. Screening for an improved GTP cyclohydrolase II mutant
FEBS J.
276
4119-4129
2009
Bacillus subtilis
brenda
Sengupta, S.; Chandra, T.
Molecular and structural characterization of GTP-cyclohydrolase II in Eremothecium ashbyi NRRL Y-1363: cDNA cloning, comparative sequence analysis and molecular modeling
Fungal Biol.
114
731-738
2010
Eremothecium ashbyi (A6MYZ0), Eremothecium ashbyi, Eremothecium ashbyi NRRL Y-1363 (A6MYZ0), Eremothecium ashbyi NRRL Y-1363
brenda
Singh, M.; Kumar, P.; Karthikeyan, S.
Structural basis for pH dependent monomer-dimer transition of 3,4-dihydroxy 2-butanone-4-phosphate synthase domain from Mycobacterium tuberculosis
J. Struct. Biol.
174
374-384
2011
Mycobacterium tuberculosis
brenda
Asai, S.; Mase, K.; Yoshioka, H.
A key enzyme for flavin synthesis is required for nitric oxide and reactive oxygen species production in disease resistance
Plant J.
62
911-924
2010
Nicotiana benthamiana (D6RUS9), Nicotiana benthamiana
brenda
Singh, M.; Kumar, P.; Yadav, S.; Gautam, R.; Sharma, N.; Karthikeyan, S.
The crystal structure reveals the molecular mechanism of bifunctional 3,4-dihydroxy-2-butanone 4-phosphate synthase/GTP cyclohydrolase II (Rv1415) from Mycobacterium tuberculosis
Acta Crystallogr. Sect. D
69
1633-1644
2013
Mycobacterium tuberculosis (P9WHF1), Mycobacterium tuberculosis, Mycobacterium tuberculosis H37Rv (P9WHF1)
brenda
Graewert, T.; Fischer, M.; Bacher, A.
Structures and reaction mechanisms of GTP cyclohydrolases
IUBMB Life
65
310-322
2013
Escherichia coli (P0A7I7)
brenda
Joo, M.; Yoo, H.; Kim, H.; Kwon, H.
ToxB encodes a canonical GTP cyclohydrolase II in toxoflavin biosynthesis and ribA expression restored toxoflavin production in a DELTAtoxB mutant
J. Korean Soc. Appl. Biol. Chem.
58
877-885
2015
Burkholderia glumae (Q8RS38), Burkholderia glumae BGR1 (Q8RS38)
-
brenda
Yadav, S.; Karthikeyan, S.
Structural and biochemical characterization of GTP cyclohydrolase II from Helicobacter pylori reveals its redox dependent catalytic activity
J. Struct. Biol.
192
100-115
2015
Helicobacter pylori (O08315), Helicobacter pylori, Helicobacter pylori ATCC 700392 (O08315)
brenda
Lister, J.
Larval but not adult xanthophore pigmentation in zebrafish requires GTP cyclohydrolase 2 (gch2) function
Pigment Cell Melanoma Res.
32
724-727
2019
Danio rerio (Q6IQV5)
-
brenda
Nasuno, R.; Suzuki, S.; Oiki, S.; Hagiwara, D.; Takagi, H.
Identification and functional analysis of GTP cyclohydrolase II in Candida glabrata in response to nitrosative stress
Front. Microbiol.
13
825121
2022
Nakaseomyces glabratus (Q6FUD7), Nakaseomyces glabratus KUE100-1 (Q6FUD7)
brenda
Anam, K.; Nasuno, R.; Takagi, H.
A novel mechanism for nitrosative stress tolerance dependent on GTP cyclohydrolase II activity involved in riboflavin synthesis of yeast
Sci. Rep.
10
6015
2020
Saccharomyces cerevisiae (P38066), Saccharomyces cerevisiae ATCC 204508 (P38066)
brenda
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