Table 3.
Kinetic and thermodynamic parameters for binding to full length rhC5acore and its mutants.
| Enzyme: product | ka × 104 (M−1 s−1)a | kd × 10−3 (s−1)a | KD (nM)a | ΔG°bind (kcal/mol)b |
|---|---|---|---|---|
| ScpAS512A:rhC5acore | 4.50 ± 0.11 | 7.5 ± 0.2 | 170 ± 10 | −9.23 |
| ScpAS512A:R37Acore | 3.33 ± 0.02 | 15.10 ± 0.13 | 453 ± 5 | −8.645 |
| ScpAS512A:R40Acore | 1.93 ± 0.10 | 25.8 ± 0.3 | 1340 ± 70 | −8.004 |
| ScpAS512A:R46Acore | 2.20 ± 0.05 | 15.21 ± 0.41 | 691 ± 4 | −8.395 |
| D783AS512A:rhC5acore | 1.097 ± 0.031 | 21.6 ± 0.5 | 1970 ± 80 | −7.775 |
| D783AS512A:R37Acore | ND | ND | 10000 ± 1000c,d | −6.80 |
| D783AS512A:R40Acore | ND | ND | 15000 ± 1000c,d | −6.57 |
| D783AS512A:R46Acore | ND | ND | 4330 ± 110c | −7.309 |
| E864AS512A:rhC5acore | 4.93 ± 0.06 | 4.38 ± 0.04 | 88.7 ± 0.6 | −9.610 |
| E864AS512A:R37Acore | 2.28 ± 0.08 | 12.1 ± 0.2 | 532 ± 19 | −8.550 |
| E864AS512A:R40Acore | 2.61 ± 0.11 | 19.5 ± 0.1 | 751 ± 26 | −8.346 |
| E864AS512A:R46Acore | 2.12 ± 0.05 | 13.2 ± 0.1 | 624 ± 11 | −8.456 |
| D889AS512A:rhC5acore | 4.44 ± 0.02 | 4.0 ± 0.1 | 90 ± 3 | −9.60 |
| D889AS512A:R37Acore | 3.01 ± 0.03 | 11.54 ± 0.17 | 384 ± 6 | −8.743 |
| D889AS512A:R40Acore | 2.48 ± 0.04 | 18.2 ± 0.5 | 734 ± 32 | −8.359 |
| D889AS512A:R46Acore | 1.254 ± 0.062 | 12.08 ± 0.07 | 965.1 ± 54.0 | −8.1974 |
a
Reported as mean and standard deviation from 3 experiments.
b
ΔG°bind = RTln[KD], R = 1.986 (cal/mol K−1), T = 298 K.
c
KD values ± SE obtained from equilibrium binding analysis of data from 3 experiments.
d
KD values are lowest estimates limited by the highest ligate concentration of 11,500 nM used in the analysis.