TABLE 3.
Activities of Abf51A, Abf51Btrunc, Abn43A, and Abn43Ba
| Enzyme | Substrate | Mean ± SD |
|||
|---|---|---|---|---|---|
| SA (U/mg) | Km (g liter−1 or mmol liter−1)b | kcat (103 min−1) | kcat/Km (103 g/liter min−1 or 103 mmol/liter min−1) | ||
| Abf51A | pNP-Araf | 118.26 ± 2.16 | 0.58 ± 0.02 | 7.48 ± 0.01 | 12.83 ± 0.21 |
| WAX | 8.71 ± 0.53 | ND | ND | ND | |
| SBA | 9.44 ± 0.13 | ND | ND | ND | |
| DA | 0 | ND | ND | ND | |
| Abf51Btrunc | pNP-Araf | 38.4 ± 0.45 | 0.42 ± 0.02 | 2.99 ± 0.03 | 7.13 ± 0.09 |
| pNP-Galf | 0.27 ± 0.02 | ND | ND | ND | |
| WAX | 0 | ND | ND | ND | |
| LAG | 0 | ND | ND | ND | |
| SBA | 0.63 ± 0.04 | ND | ND | ND | |
| DA | 13.01 ± 0.15 | ND | ND | ND | |
| Abn43A | WAX | 0 | ND | ND | ND |
| LAG | 0 | ND | ND | ND | |
| SBA | 21.21 ± 0.06 | 5.95 ± 0.31 | 2.41 ± 0.04 | 0.41 ± 0.01 | |
| DA | 9.58 ± 0.64 | 2.58 ± 0.21 | 0.87 ± 0.02 | 0.34 ± 0.01 | |
| Abn43B | A2 | 0 | ND | ND | ND |
| A3 | 17.16 ± 2.15 | 3.65 ± 1.29 | 1.84 ± 0.35 | 0.50 ± 0.27 | |
| A4 | 14.06 ± 1.60 | 0.55 ± 0,15 | 1.03 ± 0.08 | 1.88 ± 0.53 | |
| A5 | 12.98 ± 0.92 | 0.64 ± 0.20 | 0.97 ± 0.09 | 1.50 ± 0.45 | |
| A6 | 11.77 ± 2.16 | 1.26 ± 0.38 | 0.91 ± 0.10 | 0.73 ± 0.28 | |
| WAX | 0 | ND | ND | ND | |
| LAG | 0 | ND | ND | ND | |
| SBA | 0 | ND | ND | ND | |
| DA | 13.90 ± 0.20 | 1.28 ± 0.09 | 0.87 ± 0.02 | 0.68 ± 0.02 | |
a
All the substrates were assayed. Data are reported only when activity was detected. ND, not determined due to no or extremely weak activity to calculate the value.
b
For reactions involving pNP-glycosides the Km was expressed in molar terms using mmol liter−1, whereas for reactions involving complex polysaccharides the Km was expressed as g liter−1.