Cloned (Comment) | Organism |
---|---|
expressed in Escherichia coli BL21(DE3) cells | Arabidopsis thaliana |
Protein Variants | Comment | Organism |
---|---|---|
L56A | less active than the wild type enzyme | Arabidopsis thaliana |
L56C | less active than the wild type enzyme | Arabidopsis thaliana |
L56F | less active than the wild type enzyme | Arabidopsis thaliana |
L56H | less active than the wild type enzyme and releases its FAD cofactor more easily than wild type GALDH | Arabidopsis thaliana |
L56I | the mutant displays a higher turnover rate with L-galactono-1,4-lactone than the wild type enzyme | Arabidopsis thaliana |
Inhibitors | Comment | Organism | Structure |
---|---|---|---|
L-galactono-1,4-lactone | inhibitory at concentrations above 2 mM | Arabidopsis thaliana | |
additional information | no substrate inhibition with L-gulono-1,4-lactone at concentrations up to 100 mM, D-galactono-1,4-lactone, D-gulono-1,4-lactone, L-mannono-1,4-lactone, and D-galacturonic acid do not inhibit the oxidation of L-galactono-1,4-lactone, no specific inhibition by cations or anions is observed | Arabidopsis thaliana |
KM Value [mM] | KM Value Maximum [mM] | Substrate | Comment | Organism | Structure |
---|---|---|---|---|---|
0.026 | - |
phenazine methosulfate | wild type enzyme, in the presence of L-galactono-1,4-lactone, in 50 mM sodium phosphate (pH 8.8), at 25°C | Arabidopsis thaliana | |
0.034 | - |
cytochrome c | wild type enzyme, in the presence of L-galactono-1,4-lactone, in 50 mM sodium phosphate (pH 8.8), at 25°C | Arabidopsis thaliana | |
0.12 | - |
L-galactono-1,4-lactone | mutant enzyme L56H, in the presence of cytochrome c, in 50 mM sodium phosphate (pH 8.8), at 25°C | Arabidopsis thaliana | |
0.17 | - |
L-galactono-1,4-lactone | wild type enzyme, in the presence of cytochrome c, in 50 mM sodium phosphate (pH 8.8), at 25°C | Arabidopsis thaliana | |
0.28 | - |
1,4-benzoquinone | wild type enzyme, in the presence of L-galactono-1,4-lactone, in 50 mM sodium phosphate (pH 8.8), at 25°C | Arabidopsis thaliana | |
0.32 | - |
L-galactono-1,4-lactone | mutant enzyme L56I, in the presence of cytochrome c, in 50 mM sodium phosphate (pH 8.8), at 25°C | Arabidopsis thaliana | |
0.56 | - |
L-galactono-1,4-lactone | mutant enzyme L56F in the presence of cytochrome c, in 50 mM sodium phosphate (pH 8.8), at 25°C | Arabidopsis thaliana | |
0.99 | - |
L-galactono-1,4-lactone | mutant enzyme L56C, in the presence of cytochrome c, in 50 mM sodium phosphate (pH 8.8), at 25°C | Arabidopsis thaliana | |
1.7 | - |
L-galactono-1,4-lactone | mutant enzyme L56IA in the presence of cytochrome c, in 50 mM sodium phosphate (pH 8.8), at 25°C | Arabidopsis thaliana | |
13.1 | - |
L-gulono-1,4-lactone | wild type enzyme, in the presence of cytochrome c, in 50 mM sodium phosphate (pH 8.8), at 25°C | Arabidopsis thaliana |
Localization | Comment | Organism | GeneOntology No. | Textmining |
---|---|---|---|---|
mitochondrion | - |
Arabidopsis thaliana | 5739 | - |
Molecular Weight [Da] | Molecular Weight Maximum [Da] | Comment | Organism |
---|---|---|---|
55000 | - |
mature enzyme, SDS-PAGE | Arabidopsis thaliana |
56000 | - |
recombinant His-tagged enzyme, gel filtration | Arabidopsis thaliana |
58760 | - |
predicted molecular mass of mature His-tagged enzyme | Arabidopsis thaliana |
Organism | UniProt | Comment | Textmining |
---|---|---|---|
Arabidopsis thaliana | - |
- |
- |
Purification (Comment) | Organism |
---|---|
Ni-NTA agarose column chromatography and Q-Sepharose column chromatography | Arabidopsis thaliana |
Specific Activity Minimum [µmol/min/mg] | Specific Activity Maximum [µmol/min/mg] | Comment | Organism |
---|---|---|---|
7 | - |
cell extract, at pH 8.8 | Arabidopsis thaliana |
76 | - |
after purification, at pH 8.8 | Arabidopsis thaliana |
Storage Stability | Organism |
---|---|
-80°C, 50 mM sodium phosphate and 300 mM NaCl (pH 7.4), more than 12 months, 30-50% loss of activity | Arabidopsis thaliana |
Substrates | Comment Substrates | Organism | Products | Comment (Products) | Rev. | Reac. |
---|---|---|---|---|---|---|
L-galactono-1,4-lactone + 1,4-benzoquinone | - |
Arabidopsis thaliana | L-ascorbate + reduced 1,4-benzoquinone | - |
? | |
L-galactono-1,4-lactone + cytochrome c | - |
Arabidopsis thaliana | L-ascorbate + reduced cytochrome c | - |
? | |
L-galactono-1,4-lactone + phenazine methosulfate | - |
Arabidopsis thaliana | L-ascorbate + reduced phenazine methosulfate | - |
? | |
L-gulono-1,4-lactone + ferricytochrome c | - |
Arabidopsis thaliana | L-ascorbate + ferrocytochrome c | - |
? | |
additional information | D-galactono-1,4-lactone, D-gulono-1,4-lactone, L-mannono-1,4-lactone, and D-galacturonic acid are no substrates, molecular oxygen can not serve as efficient electron acceptor for the mutant enzymes | Arabidopsis thaliana | ? | - |
? |
Synonyms | Comment | Organism |
---|---|---|
ferricytochrome c oxidoreductase | - |
Arabidopsis thaliana |
GALDH | - |
Arabidopsis thaliana |
L-galactono-gamma-lactone dehydrogenase | catalyzes the final step in the biosynthesis of vitamin C in plants | Arabidopsis thaliana |
Temperature Stability Minimum [°C] | Temperature Stability Maximum [°C] | Comment | Organism |
---|---|---|---|
52 | - |
the recombinant enzyme has a half-life of 20 min at 52°C, in the presence of excess FAD the half-life at 52°C is increased to 115 min | Arabidopsis thaliana |
Turnover Number Minimum [1/s] | Turnover Number Maximum [1/s] | Substrate | Comment | Organism | Structure |
---|---|---|---|---|---|
4 | - |
L-gulono-1,4-lactone | in the presence of cytochrome c, in 50 mM sodium phosphate (pH 8.8), at 25°C | Arabidopsis thaliana | |
32 | - |
L-galactono-1,4-lactone | mutant enzyme L56H, in the presence of cytochrome c, in 50 mM sodium phosphate (pH 8.8), at 25°C | Arabidopsis thaliana | |
45 | - |
L-galactono-1,4-lactone | mutant enzyme L56IA in the presence of cytochrome c, in 50 mM sodium phosphate (pH 8.8), at 25°C | Arabidopsis thaliana | |
64 | - |
phenazine methosulfate | in the presence of L-galactono-1,4-lactone, in 50 mM sodium phosphate (pH 8.8), at 25°C | Arabidopsis thaliana | |
76 | - |
L-galactono-1,4-lactone | mutant enzyme L56C, in the presence of cytochrome c, in 50 mM sodium phosphate (pH 8.8), at 25°C | Arabidopsis thaliana | |
108 | - |
1,4-benzoquinone | in the presence of L-galactono-1,4-lactone, in 50 mM sodium phosphate (pH 8.8), at 25°C | Arabidopsis thaliana | |
126 | - |
L-galactono-1,4-lactone | mutant enzyme L56F in the presence of cytochrome c, in 50 mM sodium phosphate (pH 8.8), at 25°C | Arabidopsis thaliana | |
134 | - |
L-galactono-1,4-lactone | wild type enzyme, in the presence of cytochrome c, in 50 mM sodium phosphate (pH 8.8), at 25°C | Arabidopsis thaliana | |
151 | - |
cytochrome c | in the presence of L-galactono-1,4-lactone, in 50 mM sodium phosphate (pH 8.8), at 25°C | Arabidopsis thaliana | |
240 | - |
L-galactono-1,4-lactone | mutant enzyme L56I, in the presence of cytochrome c, in 50 mM sodium phosphate (pH 8.8), at 25°C | Arabidopsis thaliana |
pH Optimum Minimum | pH Optimum Maximum | Comment | Organism |
---|---|---|---|
8.8 | - |
for activity with cytochrome c | Arabidopsis thaliana |
pH Minimum | pH Maximum | Comment | Organism |
---|---|---|---|
8 | 9.5 | for activity with cytochrome c | Arabidopsis thaliana |
Cofactor | Comment | Organism | Structure |
---|---|---|---|
FAD | flavoenzyme with noncovalently bound FAD | Arabidopsis thaliana | |
ferricytochrome c | - |
Arabidopsis thaliana |
Ki Value [mM] | Ki Value maximum [mM] | Inhibitor | Comment | Organism | Structure |
---|---|---|---|---|---|
16.4 | - |
L-galactono-1,4-lactone | at 25°C | Arabidopsis thaliana |
Organism | Comment | pI Value Maximum | pI Value |
---|---|---|---|
Arabidopsis thaliana | theoretical value for recombinant His-tagged GALDH | - |
6.8 |