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3,5,7,2',4'-pentahydroxyflavone + O2
?
3,5,7,3',4',5'-hexahydroxyflavone + O2
?
3,5,7,4'-tetrahydroxyflavone + O2
?
3,5,7-trihydroxyflavone + O2
?
3,7,3',4'-tetrahydroxyflavone + O2
?
-
35% of the activity with quercetin, Co-QueD, 15% of the activity with quercetin, Ni-QueD
-
-
?
fisetin + O2
2-[[(3,4-dihydroxyphenyl)carbonyl]oxy]-4-hydroxybenzoate + CO
galangin + O2
2,4-dihydroxy-6-[(phenylcarbonyl)oxy]benzoate + CO
morin + O2
?
i.e. 3,5,7,2',4'-pentahydroxyflavone, 1.7% of the activity with quercetin
-
-
?
quercetin + O2
2-(3,4-dihydroxybenzoyloxy)-4,6-dihydroxybenzoate + CO
quercetin + O2
2-(3,4-dihydroxybenzoyloxy)-4,6-dihydroxybenzoate + CO + H+
quercetin + O2
2-protocatechoylphloroglucinolcarboxylate + CO
tamarixetin + O2
2,4-dihydroxy-6-[[(3-hydroxy-4-methoxyphenyl)carbonyl]oxy]benzoate + CO
additional information
?
-
3,5,7,2',4'-pentahydroxyflavone + O2
?
-
5.5% of the activity with quercetin, Co-QueD, 0.9% of the activity with quercetin, Ni-QueD
-
-
?
3,5,7,2',4'-pentahydroxyflavone + O2
?
-
5.5% of the activity with quercetin, Co-QueD, 0.9% of the activity with quercetin, Ni-QueD
-
-
?
3,5,7,3',4',5'-hexahydroxyflavone + O2
?
-
77% of the activity with quercetin, Co-QueD, 46% of the activity with quercetin, Ni-QueD
-
-
?
3,5,7,3',4',5'-hexahydroxyflavone + O2
?
-
77% of the activity with quercetin, Co-QueD, 46% of the activity with quercetin, Ni-QueD
-
-
?
3,5,7,4'-tetrahydroxyflavone + O2
?
-
43% of the activity with quercetin, Co-QueD, 29% of the activity with quercetin, Ni-QueD
-
-
?
3,5,7,4'-tetrahydroxyflavone + O2
?
-
43% of the activity with quercetin, Co-QueD, 29% of the activity with quercetin, Ni-QueD
-
-
?
3,5,7-trihydroxyflavone + O2
?
-
13% of the activity with quercetin, Co-QueD, 16% of the activity with quercetin, Ni-QueD
-
-
?
3,5,7-trihydroxyflavone + O2
?
-
13% of the activity with quercetin, Co-QueD, 16% of the activity with quercetin, Ni-QueD
-
-
?
fisetin + O2
2-[[(3,4-dihydroxyphenyl)carbonyl]oxy]-4-hydroxybenzoate + CO
-
1.22% activity compared to quercetin
-
-
?
fisetin + O2
2-[[(3,4-dihydroxyphenyl)carbonyl]oxy]-4-hydroxybenzoate + CO
-
1.22% activity compared to quercetin
-
-
?
fisetin + O2
?
16.8% of the activity with quercetin
-
-
?
fisetin + O2
?
i.e. 3,7,3',4'-tetrahydroxyflavone, 23% of the activity with quercetin
-
-
?
fisetin + O2
?
i.e. 3,7,3',4'-tetrahydroxyflavone, 23% of the activity with quercetin
-
-
?
galangin + O2
2,4-dihydroxy-6-[(phenylcarbonyl)oxy]benzoate + CO
-
110% activity compared to quercetin
-
-
?
galangin + O2
2,4-dihydroxy-6-[(phenylcarbonyl)oxy]benzoate + CO
-
110% activity compared to quercetin
-
-
?
galangin + O2
?
21% of the activity with quercetin
-
-
?
galangin + O2
?
i.e. 3,5,7-trihydroxyflavone, 28% of the activity with quercetin
-
-
?
galangin + O2
?
i.e. 3,5,7-trihydroxyflavone, 28% of the activity with quercetin
-
-
?
kaempferol + O2
?
activity is 2.18fold higher than with quercetin
-
-
?
kaempferol + O2
?
i.e. 3,5,7,4'-tetrahydroxyflavone. 70% of the activity with quercetin
-
-
?
myricetin + O2
?
-
-
-
?
myricetin + O2
?
i.e. 3,5,7,3',4',5'-hexahydroxyflavone. 49% of the activity with quercetin
-
-
?
myricetin + O2
?
i.e. 3,5,7,3',4',5'-hexahydroxyflavone. 49% of the activity with quercetin
-
-
?
quercetin + O2
2-(3,4-dihydroxybenzoyloxy)-4,6-dihydroxybenzoate + CO
-
-
-
?
quercetin + O2
2-(3,4-dihydroxybenzoyloxy)-4,6-dihydroxybenzoate + CO
-
-
-
?
quercetin + O2
2-(3,4-dihydroxybenzoyloxy)-4,6-dihydroxybenzoate + CO
transcription of queD is triggered by quercetin and its 3-O-rhamnosylglucoside rutin, but not by the flavonol morin (3,5,7,2',4'-pentahydroxyflavone), the presumed quercetin degradation products protocatechuate and 2,4,6-trihydroxybenzoate or the sugars rhamnose and glucose. Quercetin-induced queD expression is not influenced by the presence of Ni(II)
-
-
?
quercetin + O2
2-(3,4-dihydroxybenzoyloxy)-4,6-dihydroxybenzoate + CO
-
-
-
?
quercetin + O2
2-(3,4-dihydroxybenzoyloxy)-4,6-dihydroxybenzoate + CO
transcription of queD is triggered by quercetin and its 3-O-rhamnosylglucoside rutin, but not by the flavonol morin (3,5,7,2',4'-pentahydroxyflavone), the presumed quercetin degradation products protocatechuate and 2,4,6-trihydroxybenzoate or the sugars rhamnose and glucose. Quercetin-induced queD expression is not influenced by the presence of Ni(II)
-
-
?
quercetin + O2
2-(3,4-dihydroxybenzoyloxy)-4,6-dihydroxybenzoate + CO + H+
-
-
-
-
?
quercetin + O2
2-(3,4-dihydroxybenzoyloxy)-4,6-dihydroxybenzoate + CO + H+
the mechanism consists in four successive steps, the first one concerns addition of O2 on the C2 carbon atom, the second corresponds to the closure of the endoperoxo intermediate. In the two last steps, bonds are broken to produce the depside and carbon monoxide. Addition of dioxygen on the C2 atom (step 1) is associated to a pyramidalization at the C2 carbon atom and to a rotation of the B-ring with respect to the conjugated A-C rings. The second step is the rate limiting one and the free energy barriers characterized for the four flavonoids are very close, reaching about 24 kcal/mol. Differences in the values are not significant enough to be exploited to rationalize the nonlinear evolution of the degradation rate. Moreover, the relatively high energy value is expected to be lowered by taking into account the whole environment
-
-
?
quercetin + O2
2-(3,4-dihydroxybenzoyloxy)-4,6-dihydroxybenzoate + CO + H+
-
cleavages of the C2-C3 and C3-C4 bonds of quercetin (Que) catalyzed by 2,4-QDs
-
-
?
quercetin + O2
2-(3,4-dihydroxybenzoyloxy)-4,6-dihydroxybenzoate + CO + H+
-
-
-
-
?
quercetin + O2
2-(3,4-dihydroxybenzoyloxy)-4,6-dihydroxybenzoate + CO + H+
-
quercetin dioxygenase catalyzes the oxidation of the flavonol quercetin with dioxygen, cleaving the central heterocyclic ring and releasing CO
-
-
?
quercetin + O2
2-(3,4-dihydroxybenzoyloxy)-4,6-dihydroxybenzoate + CO + H+
-
-
-
-
?
quercetin + O2
2-(3,4-dihydroxybenzoyloxy)-4,6-dihydroxybenzoate + CO + H+
-
-
-
-
?
quercetin + O2
2-(3,4-dihydroxybenzoyloxy)-4,6-dihydroxybenzoate + CO + H+
-
-
-
?
quercetin + O2
2-(3,4-dihydroxybenzoyloxy)-4,6-dihydroxybenzoate + CO + H+
-
-
-
-
?
quercetin + O2
2-(3,4-dihydroxybenzoyloxy)-4,6-dihydroxybenzoate + CO + H+
-
-
-
?
quercetin + O2
2-(3,4-dihydroxybenzoyloxy)-4,6-dihydroxybenzoate + CO + H+
-
-
-
?
quercetin + O2
2-protocatechoylphloroglucinolcarboxylate + CO
-
-
-
-
?
quercetin + O2
2-protocatechoylphloroglucinolcarboxylate + CO
-
-
-
?
quercetin + O2
2-protocatechoylphloroglucinolcarboxylate + CO
-
-
-
?
quercetin + O2
2-protocatechoylphloroglucinolcarboxylate + CO
-
-
-
-
?
quercetin + O2
2-protocatechoylphloroglucinolcarboxylate + CO
-
low activity
-
-
?
quercetin + O2
2-protocatechoylphloroglucinolcarboxylate + CO
-
quercetin is a flavonol
-
-
?
quercetin + O2
2-protocatechoylphloroglucinolcarboxylate + CO
-
-
-
-
?
quercetin + O2
2-protocatechoylphloroglucinolcarboxylate + CO
-
low activity
-
-
?
quercetin + O2
2-protocatechoylphloroglucinolcarboxylate + CO
-
-
-
-
?
quercetin + O2
2-protocatechoylphloroglucinolcarboxylate + CO
-
low activity
-
-
?
quercetin + O2
2-protocatechoylphloroglucinolcarboxylate + CO
-
-
-
-
?
quercetin + O2
2-protocatechoylphloroglucinolcarboxylate + CO
-
low activity
-
-
?
quercetin + O2
2-protocatechoylphloroglucinolcarboxylate + CO
-
-
-
-
?
quercetin + O2
2-protocatechoylphloroglucinolcarboxylate + CO
-
low activity
-
-
?
quercetin + O2
2-protocatechoylphloroglucinolcarboxylate + CO
-
-
-
-
?
quercetin + O2
2-protocatechoylphloroglucinolcarboxylate + CO
-
low activity
-
-
?
quercetin + O2
2-protocatechoylphloroglucinolcarboxylate + CO
-
-
-
-
?
quercetin + O2
2-protocatechoylphloroglucinolcarboxylate + CO
-
-
-
-
?
quercetin + O2
2-protocatechoylphloroglucinolcarboxylate + CO
-
-
-
?
quercetin + O2
2-protocatechoylphloroglucinolcarboxylate + CO
-
-
-
?
quercetin + O2
2-protocatechoylphloroglucinolcarboxylate + CO
-
-
-
-
?
quercetin + O2
2-protocatechoylphloroglucinolcarboxylate + CO
-
100% activity
-
-
?
quercetin + O2
2-protocatechoylphloroglucinolcarboxylate + CO
-
-
-
-
?
quercetin + O2
2-protocatechoylphloroglucinolcarboxylate + CO
-
100% activity
-
-
?
quercetin + O2
2-protocatechoylphloroglucinolcarboxylate + CO
-
-
-
-
?
quercetin + O2
2-protocatechoylphloroglucinolcarboxylate + CO
-
-
-
?
quercetin + O2
2-protocatechoylphloroglucinolcarboxylate + CO
-
-
-
-
?
quercetin + O2
2-protocatechoylphloroglucinolcarboxylate + CO
-
-
-
?
tamarixetin + O2
2,4-dihydroxy-6-[[(3-hydroxy-4-methoxyphenyl)carbonyl]oxy]benzoate + CO
-
82.4% activity compared to quercetin
-
-
?
tamarixetin + O2
2,4-dihydroxy-6-[[(3-hydroxy-4-methoxyphenyl)carbonyl]oxy]benzoate + CO
-
82.4% activity compared to quercetin
-
-
?
additional information
?
-
quercetin 2,3-dioxygenase is a copper-containing enzyme that catalyzes the insertion of molecular oxygen into polyphenolic flavonols
-
-
?
additional information
?
-
-
quercetin 2,3-dioxygenase is a copper-containing enzyme that catalyzes the insertion of molecular oxygen into polyphenolic flavonols
-
-
?
additional information
?
-
-
the enzyme opens up two C-C bonds of the heterocyclic ring of quercetin, a widespread plant flavonol
-
-
?
additional information
?
-
-
quercetin 2,3-dioxygenase activates molecular oxygen to catalyze the oxygenative ring-opening reaction of the O-heterocycle of quercetin to the corresponding depside (phenolic carboxylic acid esters) and carbon monoxide
-
-
?
additional information
?
-
-
a flavonolate ion (fla-, deprotonated substrate) is bound through the 3-hydroxy group to the copper(II) ion, which exhibits a distorted squarepyramidal geometry. The bound substrate is stabilized by Glu73 through a hydrogen-bonding interaction. Synthesis of a set of copper(II) complexes [CuIILn(AcO)] and their flavonolate adducts [CuIILn(fla)] with the series of carboxyl-group-containing ligands LnH, the treatment of the ligands with CuII(OAc)2xH2O gives the corresponding mononuclear copper(II) complexes [CuIILn(OAc)], dioxygenation of flavonol catalyzed by the binary complexes [CuIILn(AcO)] (multiturnover reaction), kinetics, overview
-
-
?
additional information
?
-
-
computational study on the dioxygenation reaction of the substrate flavonolate (fla) by a synthetic model complex and related species mimicking quercetin 2,4-dioxygenases, overview. The reaction mechanism obtained for the present biomimetic complexes is substantially different from the plausible enzymatic reaction. All model complexes favor a single electron transfer from flavonolate to dioxygen over a valence tautomerism, and a subsequent intersystem crossing and a ring-closure lead to a formation of a 1,2-dioxetane intermediate instead of undergoing a direct formation of a precursor endoperoxide. The generation of the 1,2-dioxetane intermediate is shown to be the rate-determining step and inclusion of a carboxylate co-ligand can enhance the reactivity, rendering this process barrier-free. Proposal of a pathway, which can circumvent a non-enzymatic reaction by involving conversion from the 1,2-dioxetane to the endoperoxide with lower barriers
-
-
?
additional information
?
-
-
the enzyme opens up two C-C bonds of the heterocyclic ring of quercetin, a widespread plant flavonol
-
-
?
additional information
?
-
-
Mn-QDO in absence of O2 shows ability to react with nitroxyl (HNO)-singly reduced form of NO. HNO is incorporated into quercetin in the same manneras dioxygen, yet the reaction is strictly regioselective, as the only product is 2-((3,4-dihydroxyphenyl)(imino)methoxy)-4,6-dihydroxybenzoate
-
-
?
additional information
?
-
-
high level of pirin leads to the resistance of poliovirus replication to quercetin by inactivating this flavonoid
-
-
?
additional information
?
-
flavonol, morin, 3,6-dihydroxyflavone and 3,7-dihydroxyflavone are transformed at a rate of less than 1% of that found for quercetin
-
-
?
additional information
?
-
-
flavonol, morin, 3,6-dihydroxyflavone and 3,7-dihydroxyflavone are transformed at a rate of less than 1% of that found for quercetin
-
-
?
additional information
?
-
-
the enzyme opens up two C-C bonds of the heterocyclic ring of quercetin, a widespread plant flavonol
-
-
?
additional information
?
-
no activity with luteolin
-
-
?
additional information
?
-
-
the enzyme opens up two C-C bonds of the heterocyclic ring of quercetin, a widespread plant flavonol
-
-
?
additional information
?
-
-
the enzyme opens up two C-C bonds of the heterocyclic ring of quercetin, a widespread plant flavonol
-
-
?
additional information
?
-
no activity with luteolin
-
-
?
Please wait a moment until the data is sorted. This message will disappear when the data is sorted.
quercetin + O2
2-(3,4-dihydroxybenzoyloxy)-4,6-dihydroxybenzoate + CO
quercetin + O2
2-(3,4-dihydroxybenzoyloxy)-4,6-dihydroxybenzoate + CO + H+
quercetin + O2
2-protocatechoylphloroglucinolcarboxylate + CO
additional information
?
-
quercetin + O2
2-(3,4-dihydroxybenzoyloxy)-4,6-dihydroxybenzoate + CO
-
-
-
?
quercetin + O2
2-(3,4-dihydroxybenzoyloxy)-4,6-dihydroxybenzoate + CO
-
-
-
?
quercetin + O2
2-(3,4-dihydroxybenzoyloxy)-4,6-dihydroxybenzoate + CO + H+
-
-
-
-
?
quercetin + O2
2-(3,4-dihydroxybenzoyloxy)-4,6-dihydroxybenzoate + CO + H+
-
-
-
-
?
quercetin + O2
2-(3,4-dihydroxybenzoyloxy)-4,6-dihydroxybenzoate + CO + H+
-
quercetin dioxygenase catalyzes the oxidation of the flavonol quercetin with dioxygen, cleaving the central heterocyclic ring and releasing CO
-
-
?
quercetin + O2
2-(3,4-dihydroxybenzoyloxy)-4,6-dihydroxybenzoate + CO + H+
-
-
-
-
?
quercetin + O2
2-(3,4-dihydroxybenzoyloxy)-4,6-dihydroxybenzoate + CO + H+
-
-
-
-
?
quercetin + O2
2-(3,4-dihydroxybenzoyloxy)-4,6-dihydroxybenzoate + CO + H+
-
-
-
?
quercetin + O2
2-(3,4-dihydroxybenzoyloxy)-4,6-dihydroxybenzoate + CO + H+
-
-
-
-
?
quercetin + O2
2-(3,4-dihydroxybenzoyloxy)-4,6-dihydroxybenzoate + CO + H+
-
-
-
?
quercetin + O2
2-(3,4-dihydroxybenzoyloxy)-4,6-dihydroxybenzoate + CO + H+
-
-
-
?
quercetin + O2
2-protocatechoylphloroglucinolcarboxylate + CO
-
-
-
-
?
quercetin + O2
2-protocatechoylphloroglucinolcarboxylate + CO
-
-
-
?
quercetin + O2
2-protocatechoylphloroglucinolcarboxylate + CO
-
-
-
?
quercetin + O2
2-protocatechoylphloroglucinolcarboxylate + CO
-
-
-
-
?
quercetin + O2
2-protocatechoylphloroglucinolcarboxylate + CO
-
quercetin is a flavonol
-
-
?
quercetin + O2
2-protocatechoylphloroglucinolcarboxylate + CO
-
-
-
-
?
quercetin + O2
2-protocatechoylphloroglucinolcarboxylate + CO
-
-
-
-
?
quercetin + O2
2-protocatechoylphloroglucinolcarboxylate + CO
-
-
-
-
?
quercetin + O2
2-protocatechoylphloroglucinolcarboxylate + CO
-
-
-
-
?
quercetin + O2
2-protocatechoylphloroglucinolcarboxylate + CO
-
-
-
-
?
quercetin + O2
2-protocatechoylphloroglucinolcarboxylate + CO
-
-
-
-
?
quercetin + O2
2-protocatechoylphloroglucinolcarboxylate + CO
-
-
-
-
?
quercetin + O2
2-protocatechoylphloroglucinolcarboxylate + CO
-
-
-
?
quercetin + O2
2-protocatechoylphloroglucinolcarboxylate + CO
-
-
-
?
quercetin + O2
2-protocatechoylphloroglucinolcarboxylate + CO
-
-
-
-
?
quercetin + O2
2-protocatechoylphloroglucinolcarboxylate + CO
-
-
-
-
?
quercetin + O2
2-protocatechoylphloroglucinolcarboxylate + CO
-
-
-
-
?
quercetin + O2
2-protocatechoylphloroglucinolcarboxylate + CO
-
-
-
-
?
additional information
?
-
quercetin 2,3-dioxygenase is a copper-containing enzyme that catalyzes the insertion of molecular oxygen into polyphenolic flavonols
-
-
?
additional information
?
-
-
quercetin 2,3-dioxygenase is a copper-containing enzyme that catalyzes the insertion of molecular oxygen into polyphenolic flavonols
-
-
?
additional information
?
-
-
the enzyme opens up two C-C bonds of the heterocyclic ring of quercetin, a widespread plant flavonol
-
-
?
additional information
?
-
-
the enzyme opens up two C-C bonds of the heterocyclic ring of quercetin, a widespread plant flavonol
-
-
?
additional information
?
-
-
high level of pirin leads to the resistance of poliovirus replication to quercetin by inactivating this flavonoid
-
-
?
additional information
?
-
-
the enzyme opens up two C-C bonds of the heterocyclic ring of quercetin, a widespread plant flavonol
-
-
?
additional information
?
-
-
the enzyme opens up two C-C bonds of the heterocyclic ring of quercetin, a widespread plant flavonol
-
-
?
additional information
?
-
-
the enzyme opens up two C-C bonds of the heterocyclic ring of quercetin, a widespread plant flavonol
-
-
?
Please wait a moment until the data is sorted. This message will disappear when the data is sorted.
Please wait a moment until the data is sorted. This message will disappear when the data is sorted.
HNO
-
nitrosyl hydride replaces dioxygen in nitroxygenase activity of manganese quercetin dioxygenase resulting in the incorporation of both N and O atoms into the product. Turnover is demonstrated by consumption of quercetin and other related substrates under anaerobic conditions in the presence of HNO-releasing compounds and the enzyme. As with dioxygenase activity, a nonenzymatic base-catalyzed reaction of quercetin with HNO isobserved above pH 7, but no enhancement of this basal reactivity is found upon addition of divalent metal salts. Unique and regioselective N-containing products are characterized by MS analysis for both the enzymatic and nonenzymatic reactions
Nickel
dioxygen shows two binding modes to the nickel ion, which can convert each other. Due to the overlap between the vacant d orbitals of nickel and the lone pair p orbitals of dioxygen and quercetin, electron transfer occurs from quercetin to dioxygen via the nickel center. Both dioxygen and quercetin can be activated by their binding to the nickel ion. The triplet reactant complex favors the catalytic reaction, and the whole reaction contains four elementary steps. A nonchemical process, the Op-Od bond rotation along the nickel center, is suggested to be rate-limiting with a free energy barrier of 19.9 kcal/mol
Co2+
-
activates
Co2+
-
can partly substitute for Mn2+
Co2+
-
Co2+ salt addition increases the activity of quercetin 2,3-dioxygenase 24fold. The Escherichia coli cultures were grown at 37°C and 200 rpm for 6 h, induced with isopropyl beta-D-thiogalactopyanoside to a final concentraton of 50 mg/l in the presence of 10 microM CoCl2, and allow to grow additional 4 h at 25°C. The protein contains 0.65-0.8 atom of cobalt and 0.1 atom of iron per subunit.
Co2+
-
supplementing the cultures of strain FLA with CoCl2 results in 1.6fold higher quercetinase activity in crude extracts
Co2+
-
can partly substitute for Ni2+
Co2+
activates, enzyme-bound
copper
single Cu(II) ion in active site
Cu
-
probably belongs to the nonblue class, two atoms per molecule of enzyme
Cu
-
0.8 mol per mol enzyme
Cu
-
1-1.6 mol per mol enzyme, nonblue type 2 Cu2+ protein
Cu
contains 0.9 copper atoms per protein
Cu2+
required, enzyme-bound, structure, overview. Manual docking, different geometries of the copper site
Cu2+
-
required, mononuclear copper(II) active site, binding structure, X-ray diffraction and NMR analysis, overview. Direct coordinative interaction between copper(II) ion and the carboxylate group of Glu73. Complexes modeling, overview
Cu2+
-
required, the copper ion is mainly coordinated by three His residues and a water molecule in a distorted tetrahedral geometry. In a minor form, the metal is penta-coordinated by three His, a glutamate, and an aquo ligand in a trigonal bipyramidal geometry. The major role of the activesite metal ion could be to correctly position the substrate and to stabilize transition states and intermediates rather than to mediate electron transfer
Cu2+
-
activates, Cu2+-containing quercetin 2,4-dioxygenase
Cu2+
-
required, a flavonolate ion (fla-, deprotonated substrate) is bound through the 3-hydroxy group to the copper(II) ion, which exhibits a distorted squarepyramidal geometry
Cu2+
-
the enzyme has a mononuclear type 2 copper center, steric effects of the protein environment contribute to maintain the orientation of the substrate dissociated from the copper center. A prior rearrangement of the Cu2+-alkylperoxo complex and a subsequent hydrogen bond switching assisted by the movement of Glu73 can facilitate formation of an endoperoxide intermediate selectively
Cu2+
-
can partly substitute for Mn2+
Cu2+
-
Cu2+ salt addition increases the activity of quercetin 2,3-dioxygenase 1.4fold. The Escherichia coli cultures were grown at 37°C and 200 rpm for 6 h, induced with isopropyl beta-D-thiogalactopyanoside to a final concentraton of 50 mg/l in the presence of 10 microM CuCl2, and allow to grow additional 4 h at 25°C.
Cu2+
-
activates, Cu-QDO, during the reaction mechanism of Cu-QDO dioxygen binds to the metal ion of the Cu-QDO-quercetin complex, yielding a Cu2+-superoxo quercetin radical intermediate, which then forms a Cu2+-alkylperoxo complex, the alkylperoxo complex evolves into endoperoxide intermediate that decomposes to the product
Cu2+
-
required, the major role of the activesite metal ion could be to correctly position the substrate and to stabilize transition states and intermediates rather than to mediate electron transfer
Fe2+
-
activates
Fe2+
-
can partly substitute for Mn2+
Fe2+
-
can partly substitute for Ni2+
Fe2+
enzyme-bound, only poorly supports catalytic activity
Iron
different coordination geometry in the two active sites of the dimer
Iron
when the metal cofactor is replaced by an iron ion, the rate-limiting step switches from the Op-Od bond rotation to the collapse of the five-membered ring intermediate, corresponding to a free energy barrier of 30.3 kcal/mol
Mn2+
-
activates
Mn2+
-
required for activity
Mn2+
-
Mn2+ salt addition increases the activity of quercetin 2,3-dioxygenase 35fold. The Escherichia coli cultures were grown at 37°C and 200 rpm for 6 h, induced with isopropyl beta-D-thiogalactopyanoside to a final concentraton of 50 mg/l in the presence of 10 microM MnSO4, and allow to grow additional 4 h at 25°C. The protein containes 1.6-1.9 atoms of Mn/subunit.
Mn2+
-
preferred divalent metal ion
Mn2+
-
activates, Mn-QDO, Mn2+ i the preferred metal ion. Mn-QDO in absence of O2 shows ability to react with nitroxyl (HNO)-singly reduced form of NO. HNO is incorporated into quercetin in the same manner as dioxygen, yet the reaction is strictly regioselective, as the only product is 2-((3,4-dihydroxyphenyl)(imino) methoxy)-4,6-dihydroxybenzoate
Mn2+
-
can partly substitute for Ni2+
Mn2+
activates, enzyme-bound
Ni2+
-
activates
Ni2+
-
Ni2+ salt addition increases the activity of quercetin 2,3-dioxygenase 2.6fold. The Escherichia coli cultures were grown at 37°C and 200 rpm for 6 h, induced with isopropyl beta-D-thiogalactopyanoside to a final concentraton of 50 mg/l in the presence of 10 microM NiCl2, and allow to grow additional 4 h at 25°C.
Ni2+
-
can partly substitute for Mn2+. Nickel is a poor cofactor.
Ni2+
-
supplementing the cultures of strain FLA with NiCl2 results in 6.1fold higher quercetinase activity in crude extracts
Ni2+
-
preferred divalent metal ion
Ni2+
activates best, enzyme-bound, a nickel quercetinase. Ni2+ ions support correct folding, the catalytic activity of wild-type QueD is likely mediated by a Ni2+ center
Zn2+
-
activates
additional information
-
a non-heme redox metalloenzyme
additional information
-
fungal quercetinases appear to exclusively utilize a Cu2+ ion for catalysis
additional information
-
synthesis of a set of copper(II) complexes [CuIILn(AcO)] and their flavonolate adducts [CuIILn(fla)] with the series of carboxyl-group-containing ligands LnH, the treatment of the ligands with CuII(OAc)2xH2O gives the corresponding mononuclear copper(II) complexes [CuIILn(OAc)], ligand structures, mass spectrometric analysis, overview
additional information
-
Cd2+ does not increase the activity of quercetin 2,3-dioxygenase. The Escherichia coli cultures were grown at 37°C and 200 rpm for 6 h, induced with isopropyl beta-D-thiogalactopyanoside to a final concentraton of 50 mg/l in the presence of 10 microM CdCl2, and allow to grow additional 4 h at 25°C.
additional information
-
Fe2+ does not increase the activity of quercetin 2,3-dioxygenase. The Escherichia coli cultures were grown at 37°C and 200 rpm for 6 h, induced with isopropyl beta-D-thiogalactopyanoside to a final concentraton of 50 mg/l in the presence of 10 microM FeCl2, and allow to grow additional 4 h at 25°C.
additional information
-
Zn2+ does not increase the activity of quercetin 2,3-dioxygenase. The Escherichia coli cultures were grown at 37°C and 200 rpm for 6 h, induced with isopropyl beta-D-thiogalactopyanoside to a final concentraton of 50 mg/l in the presence of 10 microM ZnSO4, and allow to grow additional 4 h at 25°C.
additional information
-
the bacterial enzyme is capable of using different divalent metal ions for catalysis, with preference Mn2+, Co2+, Fe2+, Ni2+, Cu2+in descending order, suggesting that the redox properties of the metal are relatively unimportant for the catalytic reaction. The major role of the active site metal ion could be to correctly position the substrate and to stabilize transition states and intermediates rather than to mediate electron transfer. The recombinant enzyme is able to exchange its active-site metal ion while retaining catalytic activity
additional information
-
the enzyme from Bacillus subtilis is active with several divalent metal cofactors such as Fe, Mn, and Co, although Mn(II) is the preferred cofactor for this enzyme
additional information
-
QDO is a mononuclear metalloenzyme hosting various transition metal ions (Cu2+, Mn2+, Fe2+) in its active site depending on the origin of the protein, different metal complex structures, overview
additional information
-
fungal quercetinases appear to exclusively utilize a Cu2+ ion for catalysis
additional information
-
no increase in activity is observed when Mn2+, Fe2+, Cu2+, or Zn2+ is added to the culture medium
additional information
-
the bacterial enzyme is capable of using different divalent metal ions for catalysis, with preference Ni2+, Co2+, Mn2+, Fe2+ in descending order, suggesting that the redox properties of the metal are relatively unimportant for the catalytic reaction. The major role of the active site metal ion could be to correctly position the substrate and to stabilize transition states and intermediates rather than to mediate electron transfer
additional information
the enzyme is metal-dependent. Cu2+ and Zn2+ do not support catalytic activity. Heterologous formation of catalytically active, native QueD holoenzyme requires Ni2+, Co2+ or Mn2+, i.e. metal ions that prefer an octahedral coordination geometry, and an intact 3His/1Glu motif or a 4His environment of the metal. The observed metal occupancies suggest that metal incorporation into QueD is governed by the relative stability of the resulting metal complexes, rather than by metal abundance. Ni2+ most likely is the physiologically relevant cofactor of QueD of Streptomyces sp. FLA, metal content analysis of wild-type and mutant enzymes, detailed overview
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evolution
-
the ring-cleaving dioxygenase belongs to the cupin superfamily, characterized by a six-stranded beta-barrel fold and conserved amino acid motifs that provide the 3His or 2- or 3His-1Glu ligand environment of a divalent metal ion. The cupin domain comprises two conserved amino acid motifs with the consensus sequences G(X)5HXH(X)3-4E(X)6G (motif 1) and G(X)5-7PXG(X)2H(X)3N
evolution
-
the ring-cleaving dioxygenase belongs to the cupin superfamily, characterized by a six-stranded beta-barrel fold and conserved amino acid motifs that provide the 3His or 2- or 3His-1Glu ligand environment of a divalent metal ion. The cupin domain comprises two conserved amino acid motifs with the consensus sequences G(X)5HXH(X)3-4E(X)6G (motif 1) and G(X)5-7PXG(X)2H(X)3N
evolution
-
the ring-cleaving dioxygenase belongs to the cupin superfamily, characterized by a six-stranded beta-barrel fold and conserved amino acid motifs that provide the 3His or 2- or 3His-1Glu ligand environment of a divalent metal ion. The cupin domain comprises two conserved amino acid motifs with the consensus sequences G(X)5HXH(X)3-4E(X)6G (motif 1) and G(X)5-7PXG(X)2H(X)3N
evolution
-
the ring-cleaving dioxygenase belongs to the cupin superfamily, characterized by a six-stranded beta-barrel fold and conserved amino acid motifs that provide the 3His or 2- or 3His-1Glu ligand environment of a divalent metal ion. The cupin domain comprises two conserved amino acid motifs with the consensus sequences G(X)5HXH(X)3-4E(X)6G (motif 1) and G(X)5-7PXG(X)2H(X)3N
evolution
quercetinases are metal-dependent dioxygenases of the cupin superfamily
evolution
-
the ring-cleaving dioxygenase belongs to the cupin superfamily, characterized by a six-stranded beta-barrel fold and conserved amino acid motifs that provide the 3His or 2- or 3His-1Glu ligand environment of a divalent metal ion. The cupin domain comprises two conserved amino acid motifs with the consensus sequences G(X)5HXH(X)3-4E(X)6G (motif 1) and G(X)5-7PXG(X)2H(X)3N
-
malfunction
replacement of individual amino acids of the 3His/1Glu metal binding motif by alanine drastically reduces or abolishes quercetinase activity and affects its structural integrity. Only substitution of the glutamate ligand (E76) by histidine results in Ni- and Co-QueD variants that retain the native fold and show residual catalytic activity
malfunction
-
the mutational removal of Glu73 causes a loss of enzyme activity
malfunction
the pathogenicity of VdQase knock-out mutants generated through Agrobacterium tumefasciens-mediated transformation is significantly reduced on susceptible potato cultivar Kennebec compared to wild-type isolates. Phenotype with a higher accumulation of flavonols in the stems of infected potatoes and a higher concentration of rutin in the leaves in response to the VdQase mutants as compared to wild-type isolates
malfunction
-
the pathogenicity of VdQase knock-out mutants generated through Agrobacterium tumefasciens-mediated transformation is significantly reduced on susceptible potato cultivar Kennebec compared to wild-type isolates. Phenotype with a higher accumulation of flavonols in the stems of infected potatoes and a higher concentration of rutin in the leaves in response to the VdQase mutants as compared to wild-type isolates
-
metabolism
-
compounds TpMesMFla (TpMes = hydrotris(3-mesityl)pyrazolylborate, M = Mn, Fe, Co, Ni, Zn, Fla = 3-hydroxyflavonolate) as models for 2,4-quercetin dioxygenase. The structures differ in the degree of delocalization in the chelate ring formed through the binding of the two O donors of the flavonolate to the metal center, the resulting trend (Zn/Fe > Co > Mn > Ni) is, not in line with the one that found when investigating the redox properties of the complexes by cyclic voltammetry (Zn > Fe > Ni > Co > Mn). The complexes exhibit exceptionally well-behaved quasi-reversible redox transitions. After the O2 reaction, salicylic acid is one of the products
metabolism
-
design of model ligands 2NCOO, 3 N, 3NCOO, 4 N (L2NCOOH: 2-((benzyl(pyridin-2-ylmethyl)amino)methyl)benzoic acid, L3N: N-benzyl-1-(pyridin-2-yl)-N-(pyridin-2-ylmethyl)methanamine, L3NCOOH: 2-{[bis(pyridin-2-ylmethyl)amino]methyl}benzoic acid, L4N: tris(pyridin-2-ylmethyl)amine) and their complexes [CoIILn(fla)] (n: 2NCOO (1), 3 N (2), 3NCOO (3), 4 N (4); fla: 3-flavonolate) as ES models of the Co(II)-containing quercetin 2,4-dioxygenase. [CoLn(fla)] exhibits higher single turnover O2 reactivity to produce products similar to the enzymatic reaction, and the decreasing order of reactivity is 3 > 4 > 1 > 2. The reaction rate constant k shows linear correlation with E1/2(CoIII/II) and Epa(fla-/fla radical)
metabolism
during oxidative ring-cleaving, electron transfer occurs from the quercetin to dioxygen via the nickel ion. Both the dioxygen and substrate are activated by binding to the nickel ion. The catalytic reaction includes the first attack of the Od atom on the quercetin to form the C-O bond, the movement of the coordinated Op atom, the formation of a five-membered heterocyclic ring, and the synergetic cleavage of the O-O bond and C-C bonds. The movement of the coordinated Op atom is the rate-limiting step
metabolism
-
the nickel(II) flavonolate complex bearing a tridentate macrocyclic ligand, [NiII(Me3-TACN)(Fl)(NO3)](H2O) (Me3-TACN = 1,4,7-trimethyl-1,4,7-triazacyclononane, Fl = 3-hydroxyflavone) is a functional model for QueD. The complex shows two isomers with respect to the direction of a flavonolate ligand. Two isomers commonly are in the octahedral geometry with a bidentate of flavonolate and a monodentate of nitrate as well as a tridentate binding of the Me3-TACN ligand. The spin state is a triplet state, and the two singly occupied molecular orbitals (SOMOs) lie energetically lower than the highest (doubly) occupied molecular orbital (HOMO). The HOMO shows an electron density localized in the flavonolate ligand
metabolism
the reaction takes place via three major steps: attack of the superoxide on the C2 of the substrate pyrone ring to generate a Ni(II)-peroxide intermediate, formation of the second C-O bond between C4 and the peroxide to produce a peroxide bridge, and simultaneous cleavage of the C2-C3, C3-C4, and O1-O2 bonds with the formation of 2-protocatechuoylphloroglucinol carboxylic acid and carbon monoxide. The third step is rate-limiting, with a barrier of 17.4 kcal/mol. For the second C-O bond formation, an alternative pathway is that the peroxide attacks the C3 of the substrate pyrone ring, leading to the formation of a four-membered ring intermediate, which then undergoes concerted C2-C3 and O1-O2 bond cleavages to produce an alpha-keto acid. This pathway is associated with a barrier of 30.6 kcal/mol. When Glu74 is protonated, the 2,3-dioxygenolytic pathway, however, has a lower barrier (21.8 kcal/mol) than the 2,4-dioxygenolytic pathway
physiological function
conversion of quercetin to 2-protocatechuoylphloroglucinol carboxylic acid is catalyzed by quercetinase, i.e. flavonol 2,4-dioxygenase. The the catalytic activity of wild-type QueD is likely mediated by a Ni2+ center
physiological function
-
quercetin 2,3-dioxygenase (QDO) is an enzyme which accepts various transition metal ions as cofactors, and cleaves the heterocyclic ring of quercetin with consumption of dioxygen and release of carbon monoxide. QDO from Bacillus subtilis that binds Mn(II) displays an unprecedented nitroxygenase activity, whereby nitroxyl (HNO) is incorporated into quercetin cleavage products instead of dioxygen. The reaction proceeds with high regiospecificity, i.e. nitrogen and oxygen atoms of HNO are incorporated into specific fragments of the cleavage product. The reaction is an inherent property of the reactants, whereas the unique reactivity of Mn-QDO, as opposed to Co- or Fe-QDO that do not catalyze nitroxygenation. A nonenzymatic base-catalyzed reaction, which occurs in pH above 7.5, yields the same reaction products
physiological function
the enzyme is a cupin domain-containing protein with dioxygenase activity and quercetinase activity (VdQase) regulating Verticillium dahliaes pathogenicity in potato roots and contributing to counteraction against host defenses. Involvement of enzyme VdQase in the catabolism of quercetin and possibly other flavonols in planta. Involvement of VdQase in the interference with signaling, suggesting a role in pathogenicity. It is hypothesized that the by-product of dioxygenation 2-protocatechuoylphloroglucinolcarboxylic acid, after dissociating into phloroglucinol and protocatechuoyl moieties, becomes a starting point for benzoic acid and salicylic acid, thereby interfering with the jasmonate pathway and affecting the interaction outcome. These events may be key factors for Verticillium dahliaes in countering potato defenses and becoming notorious in the rhizosphere. Role of VdQase in rutin and quercetin utilization, overview
physiological function
-
the enzyme is a cupin domain-containing protein with dioxygenase activity and quercetinase activity (VdQase) regulating Verticillium dahliaes pathogenicity in potato roots and contributing to counteraction against host defenses. Involvement of enzyme VdQase in the catabolism of quercetin and possibly other flavonols in planta. Involvement of VdQase in the interference with signaling, suggesting a role in pathogenicity. It is hypothesized that the by-product of dioxygenation 2-protocatechuoylphloroglucinolcarboxylic acid, after dissociating into phloroglucinol and protocatechuoyl moieties, becomes a starting point for benzoic acid and salicylic acid, thereby interfering with the jasmonate pathway and affecting the interaction outcome. These events may be key factors for Verticillium dahliaes in countering potato defenses and becoming notorious in the rhizosphere. Role of VdQase in rutin and quercetin utilization, overview
-
additional information
-
enzyme-bound quercetin shields the FeII cofactor from interactions with the O2 mimic nitric oxide, tentatively suggesting that the reaction catalyzed by Bacillus (Fe-)quercetinase may proceed without direct interaction of dioxygen and metal ion, overview
additional information
Manual docking of the substrate quercetin into the active site showed that the different geometries of the copper site might be of catalytic importance
additional information
-
Manual docking of the substrate quercetin into the active site showed that the different geometries of the copper site might be of catalytic importance
additional information
-
synthesis of a series of flavonolate complexes as structural and functional models for the enzyme-substrate complexes of the active site of MII-containing quercetin 2,3-dioxygenase, structure analysis, overview
additional information
-
synthetic routes to tris(imidazolyl)carboxylate ligands, {N,N-bis[(1-methyl-1H-imidazol-4-yl-kappaN3)methyl]glycinato-kappa2N,O}(dichloro)ferrate(1-), [3-(hydroxy-kappaO)-2-phenyl-4H-chromen-4-onato-kappaO4][bis(triphenylphosphane)]copper, (1Z,3Z)-N,N'-di(pyridin-2-yl)-1H-isoindole-1,3(2H)-diimine, chloro[(4-phenoxy-1,4,7-triazonan-1-yl-kappa3N1,N4,N7)acetato-kappaO]copper,2-{4-[hydroxy(di-1H-imidazol-4-yl)methyl]-1H-imidazol-2-yl}-2-methylpropanoic acid, and 2-(4-{bis[1-methyl-2-(propan-2-yl)-1H-imidazol-4-yl]methyl}-1-methyl-1H-imidazol-2-yl)-2-methylpropanoic acid, and representative metal complexes, which provide more accurate active site models for several classes of redox metalloenzymes, complex structures, detailed overview
additional information
-
the mechanism which involves initial electron transfer from the divalent metal to O2, as proposed for the extradiol dioxygenases, requires that a MIII-superoxo state is thermodynamically accessible, overview
additional information
-
active site model, overview
additional information
-
for bacterial 2,4-QDs in which Co2+ or Ni2+ is employed as a cofactor, direct electron transfer from the activated Que to dioxygen (path C) may occur in analogy with cofactor-free dioxygenases. The subsequent radical coupling via intersystem crossing leads to an ESO2 complex, because Co2+ and Ni2+ are expected to be redox-inactive in this process
additional information
-
residue Glu73 plays an important role in the catalytic reaction
additional information
-
the mechanism which involves initial electron transfer from the divalent metal to O2, as proposed for the extradiol dioxygenases, requires that a MIII-superoxo state is thermodynamically accessible, overview
-
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Brown, S.B.; Rajananda, V.; Holroyd, J.A.; Evans, E.G.V.
A study of the mechanism of quercetin oxygenation by 18O labelling. A comparison of the mechanism with that of haem degradation
Biochem. J.
205
239-244
1982
Aspergillus flavus
brenda
Vanneste, W.H.; Zuberbuhler, A.
Copper-containing oxygenases
Mol. Mech. Oxygen Activ. (Hayaishi, O., ed.) Academic Press, New York
371-404
1974
Aspergillus flavus
-
brenda
Oka, T.; Simpson, J.; Krishnamurty, H.G.
Degradation of rutin by Aspergillus flavus. Studies on specificity, inhibition, and possible reaction mechanism of quercetinase
Can. J. Microbiol.
18
493-508
1972
Aspergillus flavus
brenda
Oka, T.; Simpson, F.J.; Child, J.J.; Mills, S.C.
Degradation of rutin by Aspergillus flavus. Purification of the dioxygenase, querecetinase
Can. J. Microbiol.
17
111-118
1971
Aspergillus flavus, Aspergillus flavus PRL 1805
brenda
Oka, T.; Simpson, F.J.
Quercetinase, a dioxygenase containing copper
Biochem. Biophys. Res. Commun.
43
1-5
1971
Aspergillus flavus
brenda
Krishnamurty, H.G.; Simpson, F.J.
Degradation of rutin by Aspergillus flavus. Studies with oxygen 18 on the action of a dioxygenase on quercetin
J. Biol. Chem.
245
1467-1471
1970
Aspergillus flavus
brenda
Hund, H.K.; Breuer, J.; Lingens, F.; Huttermann, J.; Kappl, R.; Fetzner, S.
Flavonol 2,4-dioxygenase from Aspergillus niger DSM 821, a type 2 CuII-containing glycoprotein
Eur. J. Biochem.
263
871-878
1999
Aspergillus niger
brenda
Steiner, R.A.; Kooter, I.M.; Dijkstra, B.W.
Functional analysis of the copper-dependent quercetin 2,3-dioxygenase. 1. Ligand-induced coordination changes probed by X-ray crystallography: inhibition, ordering effect, and mechanistic insights
Biochemistry
41
7955-7962
2002
Aspergillus japonicus (Q7SIC2), Aspergillus japonicus
brenda
Kooter, I.M.; Steiner, R.A.; Dijkstra, B.W.; van Noort, P.I.; Egmond, M.R.; Huber, M.
EPR characterization of the mononuclear Cu-containing Aspergillus japonicus quercetin 2,3-dioxygenase reveals dramatic changes upon anaerobic binding of substrates
Eur. J. Biochem.
269
2971-2979
2002
Aspergillus japonicus
brenda
Steiner, R.A.; Meyer-Klaucke, W.; Dijkstra, B.W.
Functional analysis of the copper-dependent quercetin 2,3-dioxygenase. 2. X-ray absorption studies of native enzyme and anaerobic complexes with the substrates quercetin and myricetin
Biochemistry
41
7963-7968
2002
Aspergillus japonicus (Q7SIC2), Aspergillus japonicus
brenda
Gopal, B.; Madan, L.L.; Betz, S.F.; Kossiakoff, A.A.
The crystal structure of a quercetin 2,3-dioxygenase from Bacillus subtilis suggests modulation of enzyme activity by a change in the metal ion at the active site(s)
Biochemistry
44
193-201
2005
Bacillus subtilis (P42106), Bacillus subtilis
brenda
Fittipaldi, M.; Steiner, R.A.; Matsushita, M.; Dijkstra, B.W.; Groenen, E.J.; Huber, M.
Single-crystal EPR study at 95 GHz of the type 2 copper site of the inhibitor-bound quercetin 2,3-dioxygenase
Biophys. J.
85
4047-4054
2003
Aspergillus japonicus (Q7SIC2), Aspergillus japonicus
brenda
Siegbahn, P.E.
Hybrid DFT study of the mechanism of quercetin 2,3-dioxygenase
Inorg. Chem.
43
5944-5953
2004
Aspergillus japonicus
brenda
van den Bosch, M.; Swart, M.; van Gunsteren, W.F.; Canters, G.W.
Simulation of the substrate cavity dynamics of quercetinase
J. Mol. Biol.
344
725-738
2004
Aspergillus japonicus (Q7SIC2)
brenda
Iacazio, G.
Increased quercetinase production by Penicillium olsonii using fractional factorial design
Process Biochem.
40
379-384
2005
Penicillium olsonii
-
brenda
Barney, B.M.; Schaab, M.R.; LoBrutto, R.; Francisco, W.A.
Evidence for a new metal in a known active site: purification and characterization of an iron-containing quercetin 2,3-dioxygenase from Bacillus subtilis
Protein Expr. Purif.
35
131-141
2004
Bacillus subtilis
brenda
Schaab, M.R.; Barney, B.M.; Francisco, W.A.
Kinetic and spectroscopic studies on the quercetin 2,3-dioxygenase from Bacillus subtilis
Biochemistry
45
1009-1016
2006
Bacillus subtilis
brenda
Merkens, H.; Sielker, S.; Rose, K.; Fetzner, S.
A new monocupin quercetinase of Streptomyces sp. FLA: identification and heterologous expression of the queD gene and activity of the recombinant enzyme towards different flavonols
Arch. Microbiol.
187
475-487
2007
Streptomyces sp. (A2VA43), Streptomyces sp. FLA / DSM 41951 (A2VA43)
brenda
Tranchimand, S.; Ertel, G.; Gaydou, V.; Gaudin, C.; Tron, T.; Iacazio, G.
Biochemical and molecular characterization of a quercetinase from Penicillium olsonii
Biochimie
90
781-789
2008
Penicillium olsonii (A7Y9J1), Penicillium olsonii
brenda
Neznanov, N.; Kondratova, A.; Chumakov, K.M.; Neznanova, L.; Kondratov, R.; Banerjee, A.K.; Gudkov, A.V.
Quercetinase pirin makes poliovirus replication resistant to flavonoid quercetin
DNA Cell Biol.
27
191-198
2008
Homo sapiens
brenda
Merkens, H.; Fetzner, S.
Transcriptional analysis of the queD gene coding for quercetinase of Streptomyces sp. FLA
FEMS Microbiol. Lett.
287
100-107
2008
Streptomyces sp. (A2VA43), Streptomyces sp. FLA / DSM 41951 (A2VA43)
brenda
Fiorucci, S.; Golebiowski, J.; Cabrol-Bass, D.; Antonczak, S.
Molecular simulations bring new insights into flavonoid/quercetinase interaction modes
Proteins
67
961-970
2007
Aspergillus japonicus (Q7SIC2)
brenda
Merkens, H.; Kappl, R.; Jakob, R.P.; Schmid, F.X.; Fetzner, S.
Quercetinase QueD of Streptomyces sp. FLA, a monocupin dioxygenase with a preference for nickel and cobalt
Biochemistry
47
12185-12196
2008
Streptomyces sp., Streptomyces sp. FLA / DSM 41951
brenda
Yadav, R.S.; Yadav, K.D.
Enzymatic characteristics of quercetinases from some indigenous Aspergillus flavus strains
Indian J. Biochem. Biophys.
45
345-349
2008
Aspergillus flavus, Aspergillus flavus MTCC-2456, Aspergillus flavus MTCC-1783, Aspergillus flavus MTCC-2206, Aspergillus flavus MTCC-1884, Aspergillus flavus MTCC-1883
brenda
Hirooka, K.; Fujita, Y.
Excess production of Bacillus subtilis quercetin 2,3-dioxygenase affects cell viability in the presence of quercetin
Biosci. Biotechnol. Biochem.
74
1030-1038
2010
Bacillus subtilis, Bacillus subtilis 168
brenda
Fetzner, S.
Ring-cleaving dioxygenases with a cupin fold
Appl. Environ. Microbiol.
78
2505-2514
2012
Aspergillus japonicus, Bacillus subtilis, Streptomyces sp., Penicillium olsonii, Streptomyces sp. FLA / DSM 41951
brenda
Sun, Y.J.; Huang, Q.Q.; Tano, T.; Itoh, S.
Flavonolate complexes of M(II) (M = Mn, Fe, Co, Ni, Cu, and Zn). Structural and functional models for the ES (enzyme-substrate) complex of quercetin 2,3-dioxygenase
Inorg. Chem.
52
10936-10948
2013
Aspergillus japonicus
brenda
Kumar, M.; Zapata, A.; Ramirez, A.; Bowen, S.; Francisco, W.; Farmer, P.
Nitrosyl hydride (HNO) replaces dioxygen in nitroxygenase activity of manganese quercetin dioxygenase
Proc. Natl. Acad. Sci. USA
108
18926-18931
2011
Bacillus subtilis
brenda
Fusetti, F., Schrter, K.H.; Steiner, R.A.; van Noort, P.I.; Pijning, T.; Rozeboom, H.J.; Kalk, K.H.; Egmond, M.R.; Dijkstra, B.W.
Crystal structure of the copper-containing quercetin 2,3-dioxygenase from Aspergillus japonicus
Structure
2
259-268
2002
Aspergillus japonicus (Q7SIC2), Aspergillus japonicus
brenda
Volkman, J.; Nicholas, K.
A synthetic quest for tris(imidazolyl) carboxylates and their metal complexes: active site models for quercetin 2,3-dioxygenases and other non-heme redox metalloenzymes
Tetrahedron
68
3368-3376
2012
Aspergillus japonicus
-
brenda
Nianios, D.; Thierbach, S.; Steimer, L.; Lulchev, P.; Klostermeier, D.; Fetzner, S.
Nickel quercetinase, a promiscuous metalloenzyme metal incorporation and metal ligand substitution studies
BMC Biochem.
16
10
2015
Streptomyces sp. FLA (A2VA43)
brenda
Sun, Y.; Li, P.; Huang, Q.; Zhang, J.; Itoh, S.
Dioxygenation of flavonol catalyzed by copper(II) complexes supported by carboxylate-containing ligands structural and functional models of quercetin 2,4-dioxygenase
Eur. J. Inorg. Chem.
2017
1845-1854
2017
Aspergillus japonicus
-
brenda
El Hadrami, A.; Islam, M.R.; Adam, L.R.; Daayf, F.
A cupin domain-containing protein with a quercetinase activity (VdQase) regulates Verticillium dahliaes pathogenicity and contributes to counteracting host defenses
Front. Plant Sci.
6
440
2015
Verticillium dahliae (G2WY50), Verticillium dahliae, Verticillium dahliae ATCC MYA-4575 (G2WY50)
brenda
Wojdyla, Z.; Borowski, T.
DFT study of the mechanism of manganese quercetin 2,3-dioxygenase quest for origins of enzyme unique nitroxygenase activity and regioselectivity
J. Biol. Inorg. Chem.
21
475-489
2016
Bacillus subtilis
brenda
Saito, T.; Kawakami, T.; Yamanaka, S.; Okumura, M.
Computational study of catalytic reaction of quercetin 2,4-dioxygenase
J. Phys. Chem. B
119
6952-6962
2015
Aspergillus japonicus
brenda
Numata, T.; Saito, T.; Kawakami, T.; Yamanaka, S.; Okumura, M.
Quantum mechanics study on synthetic model of copper-containing quercetin 2,4-dioxygenase
Polyhedron
136
45-51
2016
Aspergillus japonicus
-
brenda
Li, H.; Wang, X.; Tian, G.; Liu, Y.
Insights into the dioxygen activation and catalytic mechanism of the nickel-containing quercetinase
Catal. Sci. Technol.
8
2340-2351
2018
Streptomyces sp. FLA (A2VA43)
-
brenda
Sun, Y.; Liu, Y.; Zhang, J.; Li, Y.
Structure-reactivity relationship in ES models of Co(II)-containing quercetin 2,4-dioxygenase
ChemistrySelect
4
13974-13982
2019
synthetic construct
-
brenda
Hoof, S.; Limberg, C.
The behavior of trispyrazolylborato-metal(II)-flavonolate complexes as functional models for bacterial quercetinase-assessment of the metal impact
Inorg. Chem.
58
12843-12853
2019
synthetic construct
brenda
Jeong, D.; Sun, S.; Moon, D.; Cho, J.
A functional model for quercetin 2,4-dioxygenase Geometric and electronic structures and reactivity of a nickel(II) flavonolate complex
J. Inorg. Biochem.
226
111632
2022
synthetic construct
brenda
Wang, W.J.; Wei, W.J.; Liao, R.Z.
Deciphering the chemoselectivity of nickel-dependent quercetin 2,4-dioxygenase
Phys. Chem. Chem. Phys.
20
15784-15794
2018
Streptomyces sp. FLA (A2VA43)
brenda