Metals/Ions | Comment | Organism | Structure |
---|---|---|---|
Co2+ | activates | Aspergillus japonicus | |
Cu2+ | activates, Cu2+-containing quercetin 2,4-dioxygenase | Aspergillus japonicus | |
Fe2+ | activates | Aspergillus japonicus | |
Mn2+ | activates | Aspergillus japonicus | |
Ni2+ | activates | Aspergillus japonicus | |
Zn2+ | activates | Aspergillus japonicus |
Natural Substrates | Organism | Comment (Nat. Sub.) | Natural Products | Comment (Nat. Pro.) | Rev. | Reac. |
---|---|---|---|---|---|---|
quercetin + O2 | Aspergillus japonicus | - |
2-(3,4-dihydroxybenzoyloxy)-4,6-dihydroxybenzoate + CO + H+ | - |
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Organism | UniProt | Comment | Textmining |
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Aspergillus japonicus | - |
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Reaction | Comment | Organism | Reaction ID |
---|---|---|---|
quercetin + O2 = 2-(3,4-dihydroxybenzoyloxy)-4,6-dihydroxybenzoate + CO + H+ | possible reaction mechanisms and pathways, kinetics, detailed overview | Aspergillus japonicus |
Substrates | Comment Substrates | Organism | Products | Comment (Products) | Rev. | Reac. |
---|---|---|---|---|---|---|
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 | Aspergillus japonicus | ? | - |
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quercetin + O2 | - |
Aspergillus japonicus | 2-(3,4-dihydroxybenzoyloxy)-4,6-dihydroxybenzoate + CO + H+ | - |
? | |
quercetin + O2 | cleavages of the C2-C3 and C3-C4 bonds of quercetin (Que) catalyzed by 2,4-QDs | Aspergillus japonicus | 2-(3,4-dihydroxybenzoyloxy)-4,6-dihydroxybenzoate + CO + H+ | - |
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Synonyms | Comment | Organism |
---|---|---|
2,4-QD | - |
Aspergillus japonicus |
Cu2+-containing 2,4-QD | - |
Aspergillus japonicus |
quercetin 2,4-dioxygenase | - |
Aspergillus japonicus |
General Information | Comment | Organism |
---|---|---|
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 ESΒO2 complex, because Co2+ and Ni2+ are expected to be redox-inactive in this process | Aspergillus japonicus |