Table 1. Thermodynamics of nucleotide binding for BiP and DnaK.
ITC experiments for full-length (FL) BiP* and its two NBD constructs with and without the interdomain linker, NBD(1-413) and NBD(1-417), were repeated three times and the standard deviations for all parameters were less than 10%.
| ANP | Kd (µM) | ∆G (kcal/mol) | ∆H (kcal/mol) | -T∆S (kcal/mol) | |
|---|---|---|---|---|---|
| DnaK* FL |
ATP | 0.16 | −9.3 | 9.0 | −18.3 |
| ADP | 0.25 | −9.0 | −3.2 | −5.8 | |
| DnaK* NBD |
ATP | 0.61 | −8.9 | −4.1 | −3.7 |
| ADP | 0.17 | −9.2 | −3.3 | −6.0 | |
| BiP* FL |
ATP | 0.80 | −8.3 | 11.4 | −19.7 |
| ADP | 5.73 | −7.1 | −7.4 | 0.3 | |
| BiP* NBD(1-413) |
ATP | 7.41 | −7.0 | 12.3 | −19.3 |
| ADP | 5.27 | −7.2 | −7.4 | 0.2 | |
| BiP* NBD(1-417) |
ATP | 1.15 | −8.1 | 14.7 | −22.3 |
| ADP | 3.94 | −7.4 | −6.4 | 1.0 |
*Thermodynamic parameters for ATPase deficient DnaK (DnaK*) and its NBD construct without the interdomain linker were taken from Taneva et al (Taneva et al., 2010).