Information on EC 1.14.11.48 - xanthine dioxygenase

Please wait a moment until all data is loaded. This message will disappear when all data is loaded.
Specify your search results
Select one or more organisms in this record:
Show additional data
Do not include text mining results
Include (text mining) results (more...)
Include results (AMENDA + additional results, but less precise; more...)


The expected taxonomic range for this enzyme is: Aspergillus nidulans

EC NUMBER
COMMENTARY hide
1.14.11.48
-
RECOMMENDED NAME
GeneOntology No.
xanthine dioxygenase
-
REACTION
REACTION DIAGRAM
COMMENTARY hide
ORGANISM
UNIPROT
LITERATURE
xanthine + 2-oxoglutarate + O2 = urate + succinate + CO2
show the reaction diagram
-
-
-
-
SYSTEMATIC NAME
IUBMB Comments
xanthine,2-oxoglutarate:oxygen oxidoreductase
Requires Fe2+ and L-ascorbate. The enzyme, which was characterized from fungi, is specific for xanthine.
ORGANISM
COMMENTARY hide
LITERATURE
UNIPROT
SEQUENCE DB
SOURCE
SUBSTRATE
PRODUCT                       
REACTION DIAGRAM
ORGANISM
UNIPROT
COMMENTARY
(Substrate) hide
LITERATURE
(Substrate)
COMMENTARY
(Product) hide
LITERATURE
(Product)
Reversibility
r=reversible
ir=irreversible
?=not specified
9-methylxanthine + 2-oxoglutarate + O2
?
show the reaction diagram
-
-
-
?
xanthine + 2-oxoadipate + O2
?
show the reaction diagram
-
-
-
-
?
xanthine + 2-oxoglutarate + O2
urate + succinate + CO2
show the reaction diagram
additional information
?
-
-
no activity with pyruvate, 2-oxobutyrate, phenyl pyruvate, and 4-hydroxyphenyl pyruvate
-
-
-
NATURAL SUBSTRATES
NATURAL PRODUCTS
REACTION DIAGRAM
ORGANISM
UNIPROT
COMMENTARY
(Substrate) hide
LITERATURE
(Substrate)
COMMENTARY
(Product) hide
LITERATURE
(Product)
REVERSIBILITY
r=reversible
ir=irreversible
?=not specified
xanthine + 2-oxoglutarate + O2
urate + succinate + CO2
show the reaction diagram
-
-
-
-
?
METALS and IONS
ORGANISM
UNIPROT
COMMENTARY hide
LITERATURE
INHIBITORS
ORGANISM
UNIPROT
COMMENTARY hide
LITERATURE
IMAGE
6,8-Dihydroxypurine
Co2+
-
0.04 mM, about 65% inhibition
Cu2+
-
0.04 mM, complete inhibition
Fe2+
-
depending on the experimental conditions, Fe2+ concentrations of above 0.025 mM can lead to enzyme inhibition of the recombinant enzyme isolated from Escherichia coli, whereas the enzyme from Aspergillus nidulans is not inhibited at Fe2+ concentrations up to 0.080 mM
Mn2+
-
0.04 mM, about 80% inhibition
N-oxalylglycine
-
competes with 2-oxoglutarate
NaCl
-
0.5 M NaCl increases the Km of 2-oxoglutarate, increases the Km of xanthine and decreased the kcat
Zn2+
-
0.04 mM, complete inhibition
KM VALUE [mM]
SUBSTRATE
ORGANISM
UNIPROT
COMMENTARY hide
LITERATURE
IMAGE
0.16
2-oxoadipate
-
25C, pH 7.4, recombinant enzyme isolated from Escherichia coli
0.031 - 0.059
2-oxoglutarate
0.4 - 1.09
9-methylxanthine
0.045 - 0.554
xanthine
additional information
2-oxoglutarate
TURNOVER NUMBER [1/s]
SUBSTRATE
ORGANISM
UNIPROT
COMMENTARY hide
LITERATURE
IMAGE
7.6
2-oxoadipate
Aspergillus nidulans
-
25C, pH 7.4, recombinant enzyme isolated from Escherichia coli
2 - 67
2-oxoglutarate
0.66 - 5.9
9-methylxanthine
3 - 72
xanthine
kcat/KM VALUE [1/mMs-1]
SUBSTRATE
ORGANISM
UNIPROT
COMMENTARY hide
LITERATURE
IMAGE
340 - 2160
2-oxoglutarate
34
850 - 9500
9-methylxanthine
48777
70 - 1600
xanthine
234
Ki VALUE [mM]
INHIBITOR
ORGANISM
UNIPROT
COMMENTARY hide
LITERATURE
IMAGE
0.00012
N-oxalylglycine
-
pH 7.4, 25C
pH OPTIMUM
ORGANISM
UNIPROT
COMMENTARY hide
LITERATURE
6.9
-
assay at
7 - 8
-
the recombinant enzyme isolated from Escherichia coli exhibits a narrow pH optimum of 7.0-8.0 with pH 7.4 yielding optimal activity for Tris, MOPS, MES, imidazole, and HEPES buffers
7
-
enzyme isolated from Aspergillus nidulans
7.4
-
assay at
TEMPERATURE OPTIMUM
ORGANISM
UNIPROT
COMMENTARY hide
LITERATURE
SOURCE TISSUE
ORGANISM
UNIPROT
COMMENTARY hide
LITERATURE
SOURCE
MOLECULAR WEIGHT
ORGANISM
UNIPROT
COMMENTARY hide
LITERATURE
40000
-
12 * 40000, SDS-PAGE
500000
-
dodecamer, gel filtration
SUBUNITS
ORGANISM
UNIPROT
COMMENTARY hide
LITERATURE
dodecamer
-
12 * 40000, SDS-PAGE
POSTTRANSLATIONAL MODIFICATION
ORGANISM
UNIPROT
COMMENTARY hide
LITERATURE
glycoprotein
-
presence of O-glycosylation as well as N-glycosylation
pH STABILITY
ORGANISM
UNIPROT
COMMENTARY hide
LITERATURE
7 - 11
-
stable
731289
STORAGE STABILITY
ORGANISM
UNIPROT
LITERATURE
-80C, stable for at least 2 months
-
4C, stored in 100 mM Tris buffer (pH 7) containing 300 mM NaCl, 250 mM imidazole, 15% glycerol, and 0.005 mM Fe2+, concentrated enzyme is stable for at least 5 months
-
4C, stored in 100 mM Tris buffer (pH 8.0) containing 300 mM NaCl, 250 mM imidazole, 1 mM EDTA, and 15% glycerol, stable for at least 1 month
-
Purification/COMMENTARY
ORGANISM
UNIPROT
LITERATURE
purified from both the fungal mycelium and recombinant Escherichia coli cells
-
wild-type enzyme variants are purified from recombinant Escherichia coli cells
-
Cloned/COMMENTARY
ORGANISM
UNIPROT
LITERATURE
overproduction of His6-tagged enzyme in Aspergillus nidulans and Escherichia coli
-
wild-type and mutant enzymes
-
ENGINEERING
ORGANISM
UNIPROT
COMMENTARY hide
LITERATURE
C357A
-
enhanced activity towards 9-methylxanthine as compared to wild-type enzyme. Mutant enzyme is resistant rto thiol-specific reagents that inactivated wild-type enzyme. Elevated ferroxidase activity in the absence of substrates
D138A
-
enhanced activity towards 9-methylxanthine as compared to wild-type enzyme. Significant decrease in Ki(app) for 6,8-dihydroxypurine
D151A
-
inactive mutant enzyme
E137A
-
enhanced activity towards 9-methylxanthine as compared to wild-type enzyme. Significant decrease in Ki(app) for 6,8-dihydroxypurine
H149A
-
inactive mutant enzyme
H340A
-
mutant enzyme exhibits 0.17% of the wild-type enzyme activity
K122A
-
2fold increase in the Kd of 2-oxoglutarate compared to wild-type enzyme
N358A
-
23fold decrease in kcat/Km compared to wild-type enzyme. Significant decrease in Ki(app) for 6,8-dihydroxypurine
Q101A
-
elevated ferroxidase activity in the absence of substrates
Q356A
-
significant decrease in Ki(app) for 6,8-dihydroxypurine. Elevated ferroxidase activity in the absence of substrates