EC Number   |
Specific Activity Minimum [µmol/min/mg] |
Specific Activity Maximum [µmol/min/mg] |
Reference |
|---|
    1.4.3.22 | -999 |
- |
19.6 units/mg, 1 unit is defined as the change in absorbance of 0.1 at 470 nm/min |
391944 |
| 1.4.3.22 | -999 |
- |
DAO activity is determined by measuring of H2O2 gneration, a product of the polyamine oxidation. Samples are homogenized in 0.1 M potassium phosphate buffer, pH 6.5. Homogenate is centrifuged and the supernatant is used for assay. Reaction mixture contains 2.5 ml of 0.1 M potassium phosphate, pH 6.5, 0.2 ml 4-aminoantipyrine/N,N-dimethylaniline reaction solutions, 0.1 ml of horseradish peroxidase (250 U/ml) and 0.2 ml of the enzyme extract. The reaction is initiated by the addition of 15 microL of putrescine. Salinity stress (50 mM NaCl) causes a significant increase in DAO activity in cultivar Changchun mici roots but only a slight increase in cultivar Jinchun no. 2 roots. When salinity stress is combined with exogenous spermidine treatment, DAO activity increases in cultivar Jinchun no. 2, but only slightly in cv. Changchun mici. |
693856 |
| 1.4.3.22 | -999 |
- |
the crude extract has a specific activity of 9.1 units/mg, while the 215fold purified enzyme has a specific activity of 1962.47 units/mg. A change in absorbance at 555 nm of 0.01 per minute is considered as one unit of enzyme activity |
725810 |
| 1.4.3.22 | 0.00017 |
- |
substrate histamine, at low substrate concentration |
672492 |
| 1.4.3.22 | 0.00037 |
- |
substrate beta-phenylethylamine, at high substrate concentration |
672492 |
| 1.4.3.22 | 0.00074 |
- |
substrate tyramine, at high substrate concentration |
672492 |
| 1.4.3.22 | 0.00075 |
- |
substrate benzylamine, at high substrate concentration |
672492 |
| 1.4.3.22 | 0.00226 |
- |
substrate histamine, at high substrate concentration |
672492 |
| 1.4.3.22 | 0.012 |
- |
- |
391922 |
| 1.4.3.22 | 0.0166 |
- |
- |
391926 |
