Preparation and specification
| Appearance | White amorphous powder |
| Purity(SDS-PAGE) | ≥90.0% |
| Specific activity | ≥220.0 U/mg（Enzyme powder） |
| glucose oxidase | ≤0.01% |
| ATPase | ≤0.005% |
| catalase | ≤0.001% |
Properties
| Source | Microorganism, Sphingomyelinase | |
| EC number | EC 3.1.4.12 | |
| Molecular weight | 36 kDa (SDS-PAGE) | |
| Isoelectric point | 8.6 | |
| Michaelis constants | 2.4×10-5 M (Sphingomyelin) | |
| Inhibitors | EDTA | |
| Optimum pH | 8.0 | Fig. 1 |
| Optimum temperature | 45℃ | Fig. 2 |
| pH stability | 6.0-8.0 (37℃, 60min) | Fig. 3 |
| Thermal stability | Below 40℃ (pH 7.5, 30 min) | Fig. 4 |
| Stability | Store at -25 ～ -15 ℃ for 12 months could maintain more than 90% activity | Fig. 5 |
Applications
This enzyme is useful for enzymatic determi nation of small and density low density lipo protein when coupled with alkaline phosphat ase and choline oxidase.
Unit definition
One unit (U) is defined as the amount of enzyme which produces 1 μmol of H2O2 per min under the conditions described below.
