TABLE 4.
Isothermal titration calorimetry data of STC binding different kinesin-5 motor domains in the presence of ATP
Data include the calculated number of binding sites (N), enthalpy (ΔH) and entropy (ΔS) values, and Kd. Averaged data are shown and were obtained from 3–5 replicates per kinesin-5 protein. Furthermore, a set of replicates was obtained for three independent enzyme preparations. In all cases except Klp61F-WT, the overall ΔG for the binding reaction was approximately −9 kcal/mol. ND, not detectable.
| Motor domain | N | ΔH° | ΔS° | Kd |
|---|---|---|---|---|
| kcal/mol | cal mol−1K−1 | μm | ||
| HsEg5 | 0.93 ± 0.05 | −14.8 ± 1.3 | −17.9 ± 4.7 | 0.08 ± 0.01 |
| Klp61F-WT | ND | ND | ND | ND |
| Klp61F-L5 | 0.92 ± 0.04 | −12.7 ± 0.6 | −12.2 ± 2.1 | 0.17 ± 0.01 |
| Klp61F-L5-α3 | 0.89 ± 0.11 | −11.3 ± 0 | −7.2 ± 0.1 | 0.15 ± 0.01 |