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Information on EC 5.3.1.12 - glucuronate isomerase
for references in articles please use BRENDA:EC5.3.1.12
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EC Tree 5 Isomerases
5.3 Intramolecular oxidoreductases
5.3.1 Interconverting aldoses and ketoses, and related compounds
5.3.1.12 glucuronate isomerase
IUBMB Comments
Also converts D-galacturonate to D-tagaturonate.
The enzyme appears in viruses and cellular organisms
- 5.3.1.12
-
amidohydrolase
-
isomerization
-
cis-enediol
- d-galacturonate
- halodurans
showSynonyms
uronate isomerase, bh0493, more
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SYNONYM 
ORGANISM
UNIPROT
COMMENTARY 
LITERATURE
D-Glucuronate isomerase
-
-
-
-
D-glucuronate ketol-isomerase
-
-
-
-
Glucuronate isomerase
Isomerase, glucuronate
-
-
-
-
URI
Uronate isomerase
Uronic isomerase
-
-
-
-
additional information
Glucuronate isomerase
-
-
-
-
Uronate isomerase
-
-
-
-
additional information
A0A140N3B4
URI is a member of the amidohydrolase superfamily, AHS
additional information
-
URI is a member of the amidohydrolase superfamily, AHS
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REACTION
REACTION DIAGRAM
COMMENTARY
ORGANISM
UNIPROT
LITERATURE
D-Glucuronate = D-fructuronate
-
-
-
-
D-Glucuronate = D-fructuronate
reaction mechanisms in which an active site base abstracts the proton from C2 of D-glucuronate to form a cisenediol intermediate. The conjugate acid then transfers this proton to C1 of the cis-enediol intermediate to form D-fructuronate
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REACTION TYPE
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
isomerization
isomerization
-
-
-
-
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PATHWAY SOURCE
PATHWAYS
BRENDA
MetaCyc
beta-D-glucuronide and D-glucuronate degradation, D-galacturonate degradation I, pectin degradation II
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SYSTEMATIC NAME
IUBMB Comments
D-glucuronate aldose-ketose-isomerase
Also converts D-galacturonate to D-tagaturonate.
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CAS REGISTRY NUMBER
COMMENTARY
9023-87-4
-
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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
D-Fructuronate
?
-
Substrates: first step in the pathway of glucuronic acid metabolism and galacturonic acid metabolism
Products: -
Products: -
?
D-Galacturonate
?
-
Substrates: first step in the pathway of glucuronic acid metabolism and galacturonic acid metabolism
Products: -
Products: -
?
D-Glucuronate
?
-
Substrates: first step in the pathway of glucuronic acid metabolism and galacturonic acid metabolism
Products: -
Products: -
?
D-Tagaturonate
?
-
Substrates: first step in the pathway of glucuronic acid metabolism and galacturonic acid metabolism
Products: -
Products: -
?
D-Glucuronate
D-Fructuronate
-
Substrates: the mononuclear metal center in the active site is ligated to the C6 carboxylate and the C5 hydroxyl group of the substrate, this hydroxyl group is also hydrogen-bonded to Asp355. The C2 and C3 hydroxyl groups of the substrate are hydrogen bonded to Arg357 and the carbonyl group at C1 is hydrogen bonded to Tyr50
Products: -
Products: -
r
additional information
?
-
A0A140N3B4
Substrates: chemical mechanism and active site structure, mutational analysis, overview
Products: -
Products: -
?
additional information
?
-
-
Substrates: chemical mechanism and active site structure, mutational analysis, overview
Products: -
Products: -
?
additional information
?
-
-
Substrates: active site structure and molecular reaction mechanism, proton transfer from C2 of D-glucuronate to C1 that is initiated by the combined actions of Asp-355 from the end of ?-strand 8 and the C-5 hydroxyl of the substrate that is bound to the metal ion. Formation of the proposed cis-enediol intermediate is further facilitated by the shuttling of the proton between the C2 and C1 oxygens by the conserved Tyr50 and/or Arg355
Products: -
Products: -
?
additional information
?
-
-
Substrates: the enzyme does not participate in the metabolism of heparin or chondroitin sulfate
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
D-Fructuronate
?
-
Substrates: first step in the pathway of glucuronic acid metabolism and galacturonic acid metabolism
Products: -
Products: -
?
D-Galacturonate
?
-
Substrates: first step in the pathway of glucuronic acid metabolism and galacturonic acid metabolism
Products: -
Products: -
?
D-Glucuronate
?
-
Substrates: first step in the pathway of glucuronic acid metabolism and galacturonic acid metabolism
Products: -
Products: -
?
D-Tagaturonate
?
-
Substrates: first step in the pathway of glucuronic acid metabolism and galacturonic acid metabolism
Products: -
Products: -
?
additional information
?
-
-
Substrates: the enzyme does not participate in the metabolism of heparin or chondroitin sulfate
Products: -
Products: -
?
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COFACTOR
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
IMAGE
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METALS and IONS
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
Co2+
-
stimulation is more potent at lower concentrations than stimulation by Mn2+
Mn2+
-
maximal stimulation is higher than stimulatipn by Zn2+ or Co2+, stimulation at low concentrations is lower than stimulation by Zn2+ and Co2+
Zn2+
Zn2+
-
stimulation is more potent at lower concentrations than stimulation by Mn2+. Vmax is about 3times higher in presence of 0.1 mM Mn2+ than in presence of 0.01 mM Zn2+ or Co2+
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INHIBITOR
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
IMAGE
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KM VALUE [mM]
SUBSTRATE
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
IMAGE
additional information
additional information
A0A140N3B4
primary isotope effects on the kinetic constants with D-glucuronate and the effects of changes in solvent viscosity are consistent with product release being the rate-limiting step
-
additional information
additional information
-
primary isotope effects on the kinetic constants with D-glucuronate and the effects of changes in solvent viscosity are consistent with product release being the rate-limiting step
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TURNOVER NUMBER [1/s]
SUBSTRATE
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
IMAGE
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kcat/KM VALUE [1/mMs-1]
SUBSTRATE
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
IMAGE
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Ki VALUE [mM]
INHIBITOR
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
IMAGE
0.0021
(2S,3R,4S)-4-(hydroxycarbamoyl)-2,3,4-trihydroxybutanoate
-
at 30°C, pH 8.0
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SPECIFIC ACTIVITY [µmol/min/mg]
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
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pH OPTIMUM
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
additional information
additional information
A0A140N3B4
the pH-rate profiles for kcat and kcat/Km for URI from Escherichia coli are bellshaped and indicate that one group must be unprotonated and another residue must be protonated for catalytic activity
additional information
-
the pH-rate profiles for kcat and kcat/Km for URI from Escherichia coli are bellshaped and indicate that one group must be unprotonated and another residue must be protonated for catalytic activity
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pH RANGE
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
6 - 9
-
pH 6.0: about 30% of maximal activity, pH 9.0: about 40% of maximal activity with D-galacturonate
7.5 - 9
-
pH 7.5: about 55% of maximal activity, pH 9.0: about 75% of maximal activity with glucuronate
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TEMPERATURE OPTIMUM
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
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ORGANISM
COMMENTARY
LITERATURE
UNIPROT
SEQUENCE DB
SOURCE
Highest Expressing Human Cell Lines
Cell Line Links Show AA Sequence and Transmembrane Helices (7210 entries)
Longer loading times are possible. Please use the AA Sequence and Transmembrane Helices Search for a specific query.
Longer loading times are possible. Please use the AA Sequence and Transmembrane Helices Search for a specific query.
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PDB
SCOP
CATH
UNIPROT
ORGANISM
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MOLECULAR WEIGHT
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
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SUBUNIT
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
additional information
additional information
A0A140N3B4
structure modelling using the crystal structure of URI from Bacillus halodurans, overview
additional information
-
structure modelling using the crystal structure of URI from Bacillus halodurans, overview
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CRYSTALLIZATION (Commentary)
ORGANISM
UNIPROT
LITERATURE
complexed with Zn2+, vapour diffusion method, with 45% polypropylene glycol and 0.1 M Bis-Tris, pH 6.5
-
enzyme Bh0493 in complex with substrate D-glucuronate, D-fructuronate, or two inhibitory mimics of the cis-enediol intermediate, hanging drop method at room temperature, B16 mg/ml h0493 in 10 mM HEPES, pH 7.5, 150 mM NaCl, 10 mM methionine, 10% glycerol, 1.0 mM DTT, 0.2 mM ZnCl2, and the corresponding substrate or inhibitor at 40 mM, precipitation solutions are 20% PEG 3350 and 0.2 M sodium citrate, pH 6.0, or 25% PEG 3350, 0.1 M Tris, pH 8.5, and 0.2 M NaCl, X-ray diffraction structure determination and analysis at 1.9-2.2 A resolution
-
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PROTEIN VARIANTS
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
D238N
A0A140N3B4
site-directed mutagenesis, the mutant shows altered kinetics and zinc content compared to the wild-type enzyme
D412A
A0A140N3B4
site-directed mutagenesis, the mutant shows altered kinetics and zinc content compared to the wild-type enzyme
D412N
A0A140N3B4
site-directed mutagenesis, the mutant shows altered kinetics and zinc content compared to the wild-type enzyme
H297A
A0A140N3B4
site-directed mutagenesis, the mutant shows altered kinetics and zinc content compared to the wild-type enzyme
H297N
A0A140N3B4
site-directed mutagenesis, the mutant shows altered kinetics and zinc content compared to the wild-type enzyme
H33A
A0A140N3B4
site-directed mutagenesis, the mutant shows altered kinetics and zinc content compared to the wild-type enzyme
H33N
A0A140N3B4
site-directed mutagenesis, the mutant shows altered kinetics and zinc content compared to the wild-type enzyme
H35A
A0A140N3B4
site-directed mutagenesis, the mutant shows altered kinetics and zinc content compared to the wild-type enzyme
H35N
A0A140N3B4
site-directed mutagenesis, the mutant shows altered kinetics and zinc content compared to the wild-type enzyme
H59A
A0A140N3B4
site-directed mutagenesis, the mutant shows altered kinetics and zinc content compared to the wild-type enzyme
H59N
A0A140N3B4
site-directed mutagenesis, the mutant shows altered kinetics and zinc content compared to the wild-type enzyme
R186K
A0A140N3B4
site-directed mutagenesis, the mutant shows altered kinetics and zinc content compared to the wild-type enzyme
R186M
A0A140N3B4
site-directed mutagenesis, the mutant shows altered kinetics and zinc content compared to the wild-type enzyme
R302K
A0A140N3B4
site-directed mutagenesis, the mutant shows altered kinetics and zinc content compared to the wild-type enzyme
R302M
A0A140N3B4
site-directed mutagenesis, the mutant shows altered kinetics and zinc content compared to the wild-type enzyme
R414K
A0A140N3B4
site-directed mutagenesis, the mutant shows altered kinetics and zinc content compared to the wild-type enzyme
R414M
A0A140N3B4
site-directed mutagenesis, the mutant shows altered kinetics and zinc content compared to the wild-type enzyme
W381A
A0A140N3B4
site-directed mutagenesis, the mutant shows altered kinetics and zinc content compared to the wild-type enzyme
W381F
A0A140N3B4
site-directed mutagenesis, the mutant shows altered kinetics and zinc content compared to the wild-type enzyme
Y60A
A0A140N3B4
site-directed mutagenesis, the mutant shows altered kinetics and zinc content compared to the wild-type enzyme
Y60F
A0A140N3B4
site-directed mutagenesis, the mutant shows altered kinetics and zinc content compared to the wild-type enzyme
additional information
additional information
A0A140N3B4
construction of mutants in association with the active site structure of URI from Bacillus halodurans
additional information
-
construction of mutants in association with the active site structure of URI from Bacillus halodurans
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STORAGE STABILITY
ORGANISM
UNIPROT
LITERATURE
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PURIFICATION (Commentary)
ORGANISM
UNIPROT
LITERATURE
of the wild type and recombinant protein, ammonium sulfate fractionation, gel filtration, and ion exchange chromatography
Resource Q column chromatography and Superdex 200 gel filtration
-
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CLONED (Commentary)
ORGANISM
UNIPROT
LITERATURE
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REF.
AUTHORS
TITLE
JOURNAL
VOL.
PAGES
YEAR
ORGANISM (UNIPROT)
PUBMED ID
SOURCE
Kilgore, W.W.; Starr, M.P.
Catabolism of galacturonic and glucuronic acids by Erwinia carotovora
J. Biol. Chem.
234
2227-2235
1959
Pectobacterium carotovorum
brenda
Ashwell, G.; Wahba, A.J.; Hickman, J.
Uronic acid metabolism in bacteria: I. Purification and properties of uronic acid isomerase in Echerichia coli
J. Biol. Chem.
235
1559-1565
1960
Escherichia coli
brenda
Karapally, J.C.; Dietrich, C.P.
A uronic acid isomerase in Flavobacterium heparinum
Can. J. Biochem.
48
164-169
1970
Pedobacter heparinus
brenda
Portalier, R.C.; Robert-Baudouy, J.M.; Nemoz, G.M.
Etudes de mutations affectant les genes de structure de l'isomerase uronique et de l'oxydoreductase altronique chez Escherichia coli K12
Mol. Gen. Genet.
128
301-319
1974
Escherichia coli
brenda
Linster, C.L.; Van Schaftingen, E.
A spectrophotometric assay of D-glucuronate based on Escherichia coli uronate isomerase and mannonate dehydrogenase
Protein Expr. Purif.
37
352-360
2004
Escherichia coli
brenda
Williams, L.; Nguyen, T.; Li, Y.; Porter, T.N.; Raushel, F.M.
Uronate isomerase: a nonhydrolytic member of the amidohydrolase superfamily with an ambivalent requirement for a divalent metal ion
Biochemistry
45
7453-7462
2006
Escherichia coli (P0A8G3)
brenda
Nguyen, T.T.; Brown, S.; Fedorov, A.A.; Fedorov, E.V.; Babbitt, P.C.; Almo, S.C.; Raushel, F.M.
At the periphery of the amidohydrolase superfamily: Bh0493 from Bacillus halodurans catalyzes the isomerization of D-galacturonate to D-tagaturonate
Biochemistry
47
1194-1206
2008
Halalkalibacterium halodurans
brenda
Nguyen, T.T.; Fedorov, A.A.; Williams, L.; Fedorov, E.V.; Li, Y.; Xu, C.; Almo, S.C.; Raushel, F.M.
The mechanism of the reaction catalyzed by uronate isomerase illustrates how an isomerase may have evolved from a hydrolase within the amidohydrolase superfamily
Biochemistry
48
8879-8890
2009
Escherichia coli (A0A140N3B4), Escherichia coli, Halalkalibacterium halodurans
brenda
EXTERNAL LINKS (specific for EC-Number 5.3.1.12)
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