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Information on EC 4.3.2.4 - purine imidazole-ring cyclase
for references in articles please use BRENDA:EC4.3.2.4
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EC Tree 4 Lyases
4.3 Carbon-nitrogen lyases
4.3.2 Amidine-lyases
4.3.2.4 purine imidazole-ring cyclase
IUBMB Comments
Also acts on 2,6-diamino-5-formamido-3,4-dihydro-4-oxopyrimidine residues. Brings about the reclosure of the imidazole rings of purine residues damaged by γ-rays.
The expected taxonomic range for this enzyme is: Eukaryota, Bacteria
showSynonyms
purine imidazole-ring cyclase, more
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SYNONYM 
ORGANISM
UNIPROT
COMMENTARY 
LITERATURE
cyclase, purine imidazole ring
-
-
-
-
PurIR cyclase
-
-
-
-
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REACTION
REACTION DIAGRAM
COMMENTARY
ORGANISM
UNIPROT
LITERATURE
DNA 4,6-diamino-5-formamidopyrimidine = DNA adenine + H2O
-
-
-
-
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REACTION TYPE
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
C-N bond formation
-
-
-
-
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SYSTEMATIC NAME
IUBMB Comments
DNA-4,6-diamino-5-formamidopyrimidine C8-N9-lyase (cyclizing; DNA-adenine-forming)
Also acts on 2,6-diamino-5-formamido-3,4-dihydro-4-oxopyrimidine residues. Brings about the reclosure of the imidazole rings of purine residues damaged by gamma-rays.
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CAS REGISTRY NUMBER
COMMENTARY
95990-28-6
-
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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
DNA 2,6-diamino-4-oxo-5-formamidopyrimidine
DNA guanine + H2O
-
Substrates: imidazole-ring-opened guanine
Products: -
Products: -
?
DNA 2,6-diamino-4-oxo-5-formamidopyrimidine
DNA guanine + H2O
-
Substrates: imidazole-ring-opened guanine
Products: -
Products: -
?
DNA 2,6-diamino-4-oxo-5-formamidopyrimidine
DNA guanine + H2O
-
Substrates: imidazole-ring-opened guanine
Products: -
Products: -
?
DNA 2,6-diamino-4-oxo-5-formamidopyrimidine
DNA guanine + H2O
Escherichia coli B / ATCC 11303
-
Substrates: imidazole-ring-opened guanine
Products: -
Products: -
?
DNA 2,6-diamino-4-oxo-5-formamidopyrimidine
DNA guanine + H2O
-
Substrates: imidazole-ring-opened guanine
Products: -
Products: -
?
DNA 2,6-diamino-4-oxo-5-formamidopyrimidine
DNA guanine + H2O
-
Substrates: imidazole-ring-opened guanine
Products: -
Products: -
?
DNA 4,6-diamino-5-formamidopyrimidine
DNA adenine + H2O
-
Substrates: imidazole-ring-opened adenine, ring closure to restore C8 to N9 linkage
Products: -
Products: -
?
DNA 4,6-diamino-5-formamidopyrimidine
DNA adenine + H2O
-
Substrates: imidazole-ring-opened adenine, ring closure to restore C8 to N9 linkage
Products: -
Products: -
?
DNA 4,6-diamino-5-formamidopyrimidine
DNA adenine + H2O
-
Substrates: imidazole-ring-opened adenine, ring closure to restore C8 to N9 linkage
Products: -
Products: -
?
DNA 4,6-diamino-5-formamidopyrimidine
DNA adenine + H2O
Escherichia coli B / ATCC 11303
-
Substrates: imidazole-ring-opened adenine, ring closure to restore C8 to N9 linkage
Products: -
Products: -
?
DNA 4,6-diamino-5-formamidopyrimidine
DNA adenine + H2O
-
Substrates: imidazole-ring-opened adenine, ring closure to restore C8 to N9 linkage
Products: -
Products: -
?
DNA 4,6-diamino-5-formamidopyrimidine
DNA adenine + H2O
-
Substrates: imidazole-ring-opened adenine, ring closure to restore C8 to N9 linkage
Products: -
Products: -
?
additional information
?
-
-
Substrates: not: opened imidazole ring of 7-methylguanine-derived formamidopyrimidine in DNA
Products: -
Products: -
?
additional information
?
-
-
Substrates: repair of formamidopyrimidine lesions in DNA, reclosure of the imidazole ring to restore the C8 to N9 linkage previously cleaved by ionizing radiation
Products: -
Products: -
?
additional information
?
-
-
Substrates: not: opened imidazole ring of 7-methylguanine-derived formamidopyrimidine in DNA
Products: -
Products: -
?
additional information
?
-
-
Substrates: repair of formamidopyrimidine lesions in DNA, reclosure of the imidazole ring to restore the C8 to N9 linkage previously cleaved by ionizing radiation
Products: -
Products: -
?
additional information
?
-
-
Substrates: not: opened imidazole ring of 7-methylguanine-derived formamidopyrimidine in DNA
Products: -
Products: -
?
additional information
?
-
-
Substrates: repair of formamidopyrimidine lesions in DNA, reclosure of the imidazole ring to restore the C8 to N9 linkage previously cleaved by ionizing radiation
Products: -
Products: -
?
additional information
?
-
Escherichia coli B / ATCC 11303
-
Substrates: not: opened imidazole ring of 7-methylguanine-derived formamidopyrimidine in DNA
Products: -
Products: -
?
additional information
?
-
Escherichia coli B / ATCC 11303
-
Substrates: repair of formamidopyrimidine lesions in DNA, reclosure of the imidazole ring to restore the C8 to N9 linkage previously cleaved by ionizing radiation
Products: -
Products: -
?
additional information
?
-
-
Substrates: not: opened imidazole ring of 7-methylguanine-derived formamidopyrimidine in DNA
Products: -
Products: -
?
additional information
?
-
-
Substrates: repair of formamidopyrimidine lesions in DNA, reclosure of the imidazole ring to restore the C8 to N9 linkage previously cleaved by ionizing radiation
Products: -
Products: -
?
additional information
?
-
-
Substrates: not: opened imidazole ring of 7-methylguanine-derived formamidopyrimidine in DNA
Products: -
Products: -
?
additional information
?
-
-
Substrates: repair of formamidopyrimidine lesions in DNA, reclosure of the imidazole ring to restore the C8 to N9 linkage previously cleaved by ionizing radiation
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
additional information
?
-
-
Substrates: repair of formamidopyrimidine lesions in DNA, reclosure of the imidazole ring to restore the C8 to N9 linkage previously cleaved by ionizing radiation
Products: -
Products: -
?
additional information
?
-
-
Substrates: repair of formamidopyrimidine lesions in DNA, reclosure of the imidazole ring to restore the C8 to N9 linkage previously cleaved by ionizing radiation
Products: -
Products: -
?
additional information
?
-
-
Substrates: repair of formamidopyrimidine lesions in DNA, reclosure of the imidazole ring to restore the C8 to N9 linkage previously cleaved by ionizing radiation
Products: -
Products: -
?
additional information
?
-
Escherichia coli B / ATCC 11303
-
Substrates: repair of formamidopyrimidine lesions in DNA, reclosure of the imidazole ring to restore the C8 to N9 linkage previously cleaved by ionizing radiation
Products: -
Products: -
?
additional information
?
-
-
Substrates: repair of formamidopyrimidine lesions in DNA, reclosure of the imidazole ring to restore the C8 to N9 linkage previously cleaved by ionizing radiation
Products: -
Products: -
?
additional information
?
-
-
Substrates: repair of formamidopyrimidine lesions in DNA, reclosure of the imidazole ring to restore the C8 to N9 linkage previously cleaved by ionizing radiation
Products: -
Products: -
?
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COFACTOR
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
IMAGE
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METALS and IONS
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
additional information
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KM VALUE [mM]
SUBSTRATE
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
IMAGE
0.000007
DNA 2,6-diamino-4-oxo-5-formamidopyrimidine
-
imidazole-ring-opened guanine
0.000005
DNA 4,6-diamino-5-formamidopyrimidine
-
imidazole-ring-opened adenine
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pH OPTIMUM
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
7.4
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pH RANGE
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
6.5 - 8.5
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TEMPERATURE OPTIMUM
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
37
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ORGANISM
COMMENTARY
LITERATURE
UNIPROT
SEQUENCE DB
SOURCE
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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.
STORAGE STABILITY
ORGANISM
UNIPROT
LITERATURE
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PURIFICATION (Commentary)
ORGANISM
UNIPROT
LITERATURE
partial
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REF.
AUTHORS
TITLE
JOURNAL
VOL.
PAGES
YEAR
ORGANISM (UNIPROT)
PUBMED ID
SOURCE
Chetsanga, C.J.; Grigorian, C.
In situ enzymatic reclosure of opened imidazole rings of purines in DNA damaged by gamma-irradiation
Proc. Natl. Acad. Sci. USA
82
633-637
1985
Chlorocebus aethiops, Cricetulus griseus, Escherichia coli, Escherichia coli B / ATCC 11303, Lacticaseibacillus casei, Proteus mirabilis
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