Table 2 Summary of all-trans retinol binding parameters to IRBP. The binding of all-trans retinol to full-length IRBP and the four modules was determined by measuring the enhancement of all-trans retinol fluorescence and the quenching of protein endogenous fluorescence as a function of retinol concentration.
Protein | Binding sites (N) Kd (μM) | Enhancementa | Quenchingb |
|---|---|---|---|
Full-length IRBP | N = | 3.19 ± 0.10 | 1.93 ± 0.41 |
Kd = | 0.30 ± 0.05 | 0.66 ± 0.14 | |
Module 1 | N = | 0.83 ± 0.15 | 0.25 ± 0.10 |
Kd = | 0.44 ± 0.13 | 0.35 ± 0.08 | |
Module 2c | N = | 1.57 ± 0.04 | 1.31 ± 0.06 |
Kd = | 0.084 ± 0.022 | 0.14 ± 0.04 | |
Module 3 | N = | 1.83 ± 0.42 | 0.65 ± 0.08 |
Kd = | 1.18 ± 0.41 | 0.31 ± 0.04 | |
Module 4 | N = | 2.06 ± 0.53 | 0.12 ± 0.05 |
Kd = | 1.79 ± 0.54 | 0.64 ± 0.05 |