TABLE 5.
Mutational analyses of CelR regarding the roles of PRD and five conserved histidine residues
| Strain | PcelA-cat CAT activity (nmol [mg protein]−1 min−1) with indicated sugar(s)a
|
||
|---|---|---|---|
| Glucose | Galactose | Galactose/cellobiose | |
| celR/pBGE | 1.13 (0.54) | 0.60 (0.24) | 0.94 (0.65) |
| celR/celR+ | 3.40 (0.82) | 3.97 (0.76) | 88.86 (2.88) |
| celR/celRDPRD | 0.68 (0.09) | 0.38 (0.19) | 0.80 (0.31) |
| celR/celRH226A | 0.20 (0.20) | 0.07 (0.12) | 0.46 (0.22) |
| celR/celRH226P | 0.54 (0.21) | 0.56 (0.18) | 0.94 (0.15) |
| celR/celRH284A | 0.34 (0.28) | 5.59 (0.62) | 21.35 (4.21) |
| celR/celRH332A | 0.16 (0.28) | 0.18 (0.19) | 0.31 (0.12) |
| celR/celRH391A | 0 (0) | 0.88 (0.26) | 3.17 (0.78) |
| celR/celRH391P | 3.10 (0.65) | 5.36 (0.61) | 144.73 (16.02) |
| celR/celRH576A | 0.59 (0.14) | 1.05 (0.61) | 1.60 (0.50) |
| celR/celRH576P | 0.11 (0.10) | 0.54 (0.48) | 0.50 (0.13) |
| celR/celRH226A H284A | 1.56 (0.82) | 0.13 (0.07) | 1.56 (0.51) |
| celR/celRH332A H391P | 1.13 (0.27) | 0.34 (0.59) | 0.14 (0.24) |
| celR/celRH284A H576A | 0.63 (0.28) | 0.72 (0.15) | 0.78 (0.25) |
| celR/celRH284A H391P | 1.16 (0.06) | 5.36 (1.00) | 14.35 (1.74) |
a
Data represent the average and standard deviation (in parentheses) of three independent assays.