Table 2. Kinetic parameters for binding of macaque FH to FHbp.
| SPR Parameter, Mean ±SE a | |||||||
|---|---|---|---|---|---|---|---|
| Serum | FH Sequence Type (Residues 352 and 360) b | ELISABinding | K D (M) x 109 | k a (M-1 s-1) x 10−6 | k d (M-1) x 103 | Rmax (RU) | χ2 (RU2) |
| Macaque 44322 | HP/HP | Low | 100.3 ±24.8 | 0.18 ±0.01 | 19.0± 0.3 | 22.9 ±2.2 | 0.60 ±0.26 |
| Macaque 44333 | HP/YS | Low | 99.5 ±18.2 | 0.19 ±0.02 | 18.8± 0.5 | 14.3 ±0.5 | 0.35 ±0.08 |
| Macaque 44370 | YS/YS | Low | —- c | —- c | —- c | 3.5 | —- c |
| Macaque 44342 | HP/YP | High | 18.2 ±0.9 | 0.18 ±0.01 | 3.18 ±0.16 | 27.3 ±2.0 | 1.56 ±0.32 |
| Macaque 41941 | YS/YP | High | 10.4 ±0.3 | 0.18 ±0.02 | 1.89 ±0.21 | 42.3 ±4.4 | 2.24 ±0.63 |
| Human | ND | High | 19.8 ±0.5 | 0.19 ±0.01 | 3.82 ±0.02 | 36.4 ±0.2 | 0.87 ±0.12 |
| Human d | ND | High | 18.2 ±0.9 | 0.22 ±0.02 | 4.11 ±0.69 | 44.0 ±3.8 | 1.84 ±0.27 |
a The mean and standard error (SE) are shown for a total of five replicates performed in two independent experiments. K D, equilibrium dissociation constant; k a, association rate constant; k d, dissociation rate constant; Rmax is the maximal binding response and Chi2 (χ2) is the quality of fit of a 1:1 binding model to the data. When the χ2 value was ~5% of the Rmax value or less, the fit was considered reliable.
b Amino acids at positions 352 and 360 for each of the two alleles inferred from DNA sequencing of FH domain 6
c—, macaque with YS/YS had Rmax too low to determine kinetic parameters
d Purified FH from same human subject