Cloned (Comment) | Organism |
---|---|
expression of wild-type and mutant enzymes in Escherichia coli strain Rosetta(DE3)pLysS | Arthrobacter globiformis |
Protein Variants | Comment | Organism |
---|---|---|
additional information | substitution of Asn510 with alanine, but not with histidine, results in a change from stepwise to concerted mechanisms for the cleavages of the OH and CH bonds of choline catalyzed by the enzyme | Arthrobacter globiformis |
N510A | site-directed mutagenesis of a catalytic residue resulting in low incorporation of FAD into the protein, enzyme kinetics decrease of 4300fold in the kcat/Kcholine, 600fold in the kred, 660fold in the kcat, and 50fold in the kcat/Koxygen values | Arthrobacter globiformis |
N510D | site-directed mutagenesis of a catalytic residue resulting in low incorporation of FAD into the protein, 75% of the flavin associates noncovalently, inactive mutant | Arthrobacter globiformis |
N510H | site-directed mutagenesis of a catalytic residue resulting in low incorporation of FAD into the protein, decreases in the kcat/Kcholine, the kred, the kcat, and the kcat/Koxygen values | Arthrobacter globiformis |
N510L | site-directed mutagenesis of a catalytic residue resulting in low incorporation of FAD into the protein | Arthrobacter globiformis |
KM Value [mM] | KM Value Maximum [mM] | Substrate | Comment | Organism | Structure |
---|---|---|---|---|---|
additional information | - |
additional information | steady-state kinetics, isotopic effects, detailed overview | Arthrobacter globiformis | |
0.055 | - |
O2 | pH 10.0, 25°C, mutant N510A | Arthrobacter globiformis | |
0.48 | - |
choline | pH 10.0, 25°C, mutant N510H | Arthrobacter globiformis | |
0.535 | - |
O2 | pH 10.0, 25°C, mutant N510H | Arthrobacter globiformis | |
0.6 | - |
choline | pH 7.0, 25°C, wild-type enzyme | Arthrobacter globiformis | |
1.7 | - |
choline | pH 10.0, 25°C, mutant N510A | Arthrobacter globiformis | |
60 | - |
choline | pH 7.0, 25°C, mutant N510H | Arthrobacter globiformis | |
155 | - |
choline | pH 7.0, 25°C, mutant N510A | Arthrobacter globiformis | |
213 | - |
choline | pH 7.0, 25°C, mutant N510L | Arthrobacter globiformis |
Natural Substrates | Organism | Comment (Nat. Sub.) | Natural Products | Comment (Nat. Pro.) | Rev. | Reac. |
---|---|---|---|---|---|---|
choline + 2 O2 + H2O | Arthrobacter globiformis | - |
betaine + 2 H2O2 | - |
? |
Organism | UniProt | Comment | Textmining |
---|---|---|---|
Arthrobacter globiformis | - |
- |
- |
Source Tissue | Comment | Organism | Textmining |
---|---|---|---|
commercial preparation | - |
Arthrobacter globiformis | - |
Substrates | Comment Substrates | Organism | Products | Comment (Products) | Rev. | Reac. |
---|---|---|---|---|---|---|
betaine aldehyde + O2 + H2O | half-reaction | Arthrobacter globiformis | betaine + H2O2 | - |
? | |
choline + 2 O2 + H2O | - |
Arthrobacter globiformis | betaine + 2 H2O2 | - |
? | |
choline + O2 | half-reaction | Arthrobacter globiformis | betaine aldehyde + H2O2 | - |
? | |
additional information | flavoprotein choline oxidase catalyzes the oxidation of choline to glycine betaine with transient formation of an aldehyde intermediate and molecular oxygen as final electron acceptor | Arthrobacter globiformis | ? | - |
? |
Temperature Optimum [°C] | Temperature Optimum Maximum [°C] | Comment | Organism |
---|---|---|---|
25 | - |
assay at | Arthrobacter globiformis |
Turnover Number Minimum [1/s] | Turnover Number Maximum [1/s] | Substrate | Comment | Organism | Structure |
---|---|---|---|---|---|
0.02 | - |
choline | pH 7.0, 25°C, mutant N510L | Arthrobacter globiformis | |
0.06 | - |
choline | pH 7.0, 25°C, mutant N510A | Arthrobacter globiformis | |
0.09 | - |
O2 | pH 10.0, 25°C, mutant N510A | Arthrobacter globiformis | |
0.09 | - |
choline | pH 10.0, 25°C, mutant N510A | Arthrobacter globiformis | |
0.51 | - |
choline | pH 7.0, 25°C, mutant N510H | Arthrobacter globiformis | |
3.4 | - |
O2 | pH 10.0, 25°C, mutant N510H | Arthrobacter globiformis | |
3.4 | - |
choline | pH 10.0, 25°C, mutant N510H | Arthrobacter globiformis | |
13.4 | - |
choline | pH 7.0, 25°C, wild-type enzyme | Arthrobacter globiformis |
pH Optimum Minimum | pH Optimum Maximum | Comment | Organism |
---|---|---|---|
7 | 10 | assay at | Arthrobacter globiformis |
Cofactor | Comment | Organism | Structure |
---|---|---|---|
FAD | - |
Arthrobacter globiformis |
General Information | Comment | Organism |
---|---|---|
evolution | the enzyme belongs to the glucose-methanol-choline oxidoreductase enzyme superfamily, which shares a highly conserved His-Asn catalytic pair in the active site, Asn510 in the Arthrobacter globiformis enzyme | Arthrobacter globiformis |
malfunction | replacing Asn510 with alanine or histidine negatively affects both the reductive and oxidative half-reactions catalyzed by choline oxidase. Substitution of Asn510 with alanine, but not with histidine, results in a change from stepwise to concerted mechanisms for the cleavages of the OH and CH bonds of choline catalyzed by the enzyme | Arthrobacter globiformis |
additional information | Asn510 participating in both the reductive and oxidative half-reactions but having a minimal rle in substrate binding | Arthrobacter globiformis |
kcat/KM Value [1/mMs-1] | kcat/KM Value Maximum [1/mMs-1] | Substrate | Comment | Organism | Structure |
---|---|---|---|---|---|
0.00009 | - |
choline | pH 7.0, 25°C, mutant N510L | Arthrobacter globiformis | |
0.0004 | - |
choline | pH 7.0, 25°C, mutant N510A | Arthrobacter globiformis | |
0.0085 | - |
choline | pH 7.0, 25°C, mutant N510H | Arthrobacter globiformis | |
0.055 | - |
choline | pH 10.0, 25°C, mutant N510A | Arthrobacter globiformis | |
1.7 | - |
O2 | pH 10.0, 25°C, mutant N510A | Arthrobacter globiformis | |
6.36 | - |
O2 | pH 10.0, 25°C, mutant N510H | Arthrobacter globiformis | |
7.1 | - |
choline | pH 10.0, 25°C, mutant N510H | Arthrobacter globiformis | |
22 | - |
choline | pH 7.0, 25°C, wild-type enzyme | Arthrobacter globiformis |