Table 4.
Results of testing the specific activity of NanB sialidase from various isolation methods.
| NanB sialidase isolation method | Supernatant | Supernatant volume (ml) | Protein concentration (mg/ml) | Total protein (mg) | Sialidase activity (U/ml) | Total sialidase activity (U) | Specific activity (U/mg) |
|---|---|---|---|---|---|---|---|
| Kloroform | Tris–HCl pH 8.0 | 1 | 0.823 | 0.823 | 0.166 | 0.166 | 0.202 |
| Glysin | Sterile aquades + Glysin 1% | 1 | 0.497 | 0.497 | 0.095 | 0.095 | 0.191 |
| Freeze thaw | Potasium phosphat buffer pH 6.8 | 1 | 0.611 | 0.611 | 0.093 | 0.093 | 0.152 |
| Osmotic shock | |||||||
| a. Original | sucrose, Tris–HCl, EDTA | 1 | 0.819 | 0.819 | 0.089 | 0.089 | 0.109 |
| reverse osmosis (RO) water | 1 | 0.203 | 0.203 | 0.002 | 0.002 | 0.009 | |
| b. Addition of Ca2+ | sucrose, Tris–HCl, EDTA | 1 | 0.870 | 0.870 | 0.075 | 0.075 | 0.087 |
| reverse osmosis (RO) water | 1 | 0.249 | 0.249 | 0.008 | 0.008 | 0.034 | |
| c. Addition of lysozyme | sucrose, Tris–HCl, EDTA | 1 | 0.893 | 0.893 | 0.081 | 0.081 | 0.091 |
| reverse osmosis (RO) water | 1 | 0.198 | 0.198 | 0.013 | 0.013 | 0.067 | |
| d. Combination of Ca2+ and lysozyme | sucrose, Tris–HCl, EDTA | 1 | 0.816 | 0.816 | 0.068 | 0.068 | 0.083 |
| reverse osmosis (RO) water | 1 | 0.216 | 0.216 | 0.021 | 0.021 | 0.099 | |