Table 2.
Activity of bifidobacterial phytases on different phosphorylated substrates
| Substrate (1 mM) | % phytase activity (mean ± SD)a |
|
|---|---|---|
| PhypA | PhylA | |
| Phytate | 100 ± 0.25 | 100 ± 0.34 |
| p-Nitrophenyl-phosphate | 0.9 ± 0.42 | 1.05 ± 0.11 |
| Phosphoenolpyruvate | ND | ND |
| Acetyl-phosphate | 6.7 ± 1.8 | 2.3 ± 0.45 |
| AMP | ND | 0.4 ± 0.11 |
| ADP | ND | ND |
| ATP | ND | ND |
| Glyceraldehyde-3-phosphate | ND | ND |
| Glucose 1-phosphate | ND | ND |
| Glucose 6-phosphate | ND | ND |
| Fructose 1-phosphate | ND | ND |
| Fructose 1,6-bisphosphate | 4.9 ± 0.1 | 1.45 ± 0.45 |
a
The reactions were carried out in triplicate in 100 mM acetate buffer, pH 5.5, at 50°C. ND, no activity detected.