Crystallization (Comment) | Organism |
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crystal structure analysis, PDB ID 5NAK | Pseudomonas fluorescens |
Natural Substrates | Organism | Comment (Nat. Sub.) | Natural Products | Comment (Nat. Pro.) | Rev. | Reac. |
---|---|---|---|---|---|---|
L-kynurenine + NADPH + H+ + O2 | Pseudomonas fluorescens | - |
3-hydroxy-L-kynurenine + NADP+ + H2O | - |
? |
Organism | UniProt | Comment | Textmining |
---|---|---|---|
Pseudomonas fluorescens | Q84HF5 | - |
- |
Reaction | Comment | Organism | Reaction ID |
---|---|---|---|
L-kynurenine + NADPH + H+ + O2 = 3-hydroxy-L-kynurenine + NADP+ + H2O | mechanism of kynurenine 3-monooxygenase-catalyzed hydroxylation reaction, quantum mechanical calculations on the hydroxylation reaction of the kynurenine pathway, which involves the oxidative half-reaction with low reaction rates, modeling by cluster method, detailed overview. The modeled mechanism involves four successive transformations: Somersault rearrangement (rate-determining step), hydride shift, keto-enol tautomerization, and the dehydration with facile barriers | Pseudomonas fluorescens |
Substrates | Comment Substrates | Organism | Products | Comment (Products) | Rev. | Reac. |
---|---|---|---|---|---|---|
L-kynurenine + NADPH + H+ + O2 | - |
Pseudomonas fluorescens | 3-hydroxy-L-kynurenine + NADP+ + H2O | - |
? | |
additional information | density functional theory (DFT) calculations in the absence and in the presence of the kynurenine 3-monooxygenase (KMO) enzyme, crystal structure (PDB ID 5NAK)-based calculations involved a quantum cluster model in which the active site of the enzyme with the substrate L-Kyn is represented with 348 atoms. According to the deduced mechanism, KMO-catalyzed hydroxylation reaction takes place with four transformations. In the initial transition state, FAD delivers its peroxy hydroxyl to the L-Kyn ring, creating an sp3-hybridized carbon center. Then, the hydrogen on the hydroxyl moiety is immediately transferred back to the proximal oxygen that remains on FAD. These consequent transformations are in line with the somersault rearrangement previously described for similar enzymatic systems. The second step corresponds to a hydride shift from the sp3-hybridized carbon of the substrate ring to its adjacent carbon, producing the keto form of 3-HK. Then, keto-3-HK is transformed into its enol form (3-HK) with a water-assisted tautomerization. Lastly, FAD is oxidized with a water-assisted dehydration, which also involves 3-HK as a catalyst. Residues Asn54, Pro318, and a crystal water molecule are seen to play significant roles in the proton relays | Pseudomonas fluorescens | ? | - |
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Subunits | Comment | Organism |
---|---|---|
homodimer | - |
Pseudomonas fluorescens |
Synonyms | Comment | Organism |
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KMO | - |
Pseudomonas fluorescens |
pfKMO | - |
Pseudomonas fluorescens |
Cofactor | Comment | Organism | Structure |
---|---|---|---|
FAD | - |
Pseudomonas fluorescens | |
NADPH | - |
Pseudomonas fluorescens |