Any feedback?
Please rate this page
(enzyme.php)
(0/150)

BRENDA support

BRENDA Home
show all | hide all No of entries

Information on EC 3.5.4.25 - GTP cyclohydrolase II and Organism(s) Helicobacter pylori and UniProt Accession O08315

for references in articles please use BRENDA:EC3.5.4.25
Please wait a moment until all data is loaded. This message will disappear when all data is loaded.
EC Tree
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 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.
Specify your search results
Select one or more organisms in this record: ?
This record set is specific for:
Helicobacter pylori
UNIPROT: O08315
Show additional data
Do not include text mining results
Include (text mining) results
Include results (AMENDA + additional results, but less precise)
Word Map
hide
The taxonomic range for the selected organisms is: Helicobacter pylori
The enzyme appears in selected viruses and cellular organisms
Synonyms
gtp cyclohydrolase ii, riba2, 3,4-dihydroxy-2-butanone 4-phosphate synthase, gchii, gch ii, gtp cyclohydrolase 2, gch-ii, nbriba, gtpch-ii, gtp cyclohydrolase-ii, more
SYNONYM
ORGANISM
UNIPROT
COMMENTARY hide
LITERATURE
GTP 7,8-8,9-dihydrolase (diphosphate-forming)
-
-
-
-
GTP-8-formylhydrolase
-
-
-
-
guanosine triphosphate cyclohydrolase II
-
-
-
-
ribA
-
-
-
-
RIBIV
-
-
-
-
REACTION TYPE
ORGANISM
UNIPROT
COMMENTARY hide
LITERATURE
hydrolysis of C-N bonds
-
-
-
-
hydrolysis of phosphoesters
-
-
-
-
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.
CAS REGISTRY NUMBER
COMMENTARY hide
56214-35-8
-
SUBSTRATE
PRODUCT                       
REACTION DIAGRAM
ORGANISM
UNIPROT
COMMENTARY
(Substrate) hide
LITERATURE
(Substrate)
COMMENTARY
(Product) hide
LITERATURE
(Product)
Reversibility
r=reversible
ir=irreversible
?=not specified
GTP + 3 H2O
formate + 2,5-diamino-6-hydroxy-4-(5-phospho-D-ribosylamino)pyrimidine + diphosphate
show the reaction diagram
-
-
-
?
GTP + H2O
formate + 2,5-diamino-6-hydroxy-4-(5-phosphoribosylamino)-pyrimidine + diphosphate
show the reaction diagram
-
-
-
-
?
NATURAL SUBSTRATE
NATURAL PRODUCT
REACTION DIAGRAM
ORGANISM
UNIPROT
COMMENTARY
(Substrate) hide
LITERATURE
(Substrate)
COMMENTARY
(Product) hide
LITERATURE
(Product)
REVERSIBILITY
r=reversible
ir=irreversible
?=not specified
GTP + 3 H2O
formate + 2,5-diamino-6-hydroxy-4-(5-phospho-D-ribosylamino)pyrimidine + diphosphate
show the reaction diagram
-
-
-
?
GTP + H2O
formate + 2,5-diamino-6-hydroxy-4-(5-phosphoribosylamino)-pyrimidine + diphosphate
show the reaction diagram
-
-
-
-
?
ORGANISM
COMMENTARY hide
LITERATURE
UNIPROT
SEQUENCE DB
SOURCE
-
SwissProt
Manually annotated by BRENDA team
GENERAL INFORMATION
ORGANISM
UNIPROT
COMMENTARY hide
LITERATURE
metabolism
the enzyme is essential for pathogens. The enzyme can regulate its catalytic activity depending on the redox environment
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
CLONED (Commentary)
ORGANISM
UNIPROT
LITERATURE
expression in Escherichia coli
-
REF.
AUTHORS
TITLE
JOURNAL
VOL.
PAGES
YEAR
ORGANISM (UNIPROT)
PUBMED ID
SOURCE
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
Manually annotated by BRENDA team
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)
Manually annotated by BRENDA team