Preparation and specification
| Appearance | Yellow amorphous powder, lyophilized |
| Purity(SDS-PAGE) | ≥90.0% |
| Enzyme powder specific activity | ≥30.0 U/mg |
| Glucose-6-phosphate dehydrogenase | ≤0.01% |
| Lactate dehydrogenase | ≤0.01% |
Properties
| EC number | 4.4.1.8 (Recombinant from microorganism) | |
| Molecular weight | 54 kDa (SDS-PAGE) | |
| Isoelectric point | 6.0 | |
| Optimum pH | 7.0-8.0 | |
| Michaelis constants | 1.6 ×10-3 M (L-Cystathionine) | |
| Inhibitors | Not inhibited by NaN3 | |
| Optimum pH | 8.0 | Fig. 1 |
| Optimum temperature | 50 ℃ | Fig. 2 |
| pH stability | pH 6.0-10.0 (25 ℃, 16 h) | Fig. 3 |
| Thermal stability | Below 45℃ (pH 8.0, 30 min) | Fig. 4 |
| Storage stability | At least one year at -25～-15 ℃ | Fig. 5 |
| Stabilizers | Triton X-100, glycerol | |
Applications
This enzyme is useful for enzymatic determination of L-homocysteine when coupled with CBS and LDH in clinical analysis.
Unit definition
One unit (U) is defined as the amount of enzyme which consumes 1 μmol of NADH per min under the conditions described below.
