Comparison of Protein Dynamics Between Solution and Solid

Comparison of Protein Dynamics Between Solution and Solid 

Methyl relaxation rates were measured in the sohd and hquid samples 

It is very important to compare the solid-state order parameters based on DCs from LGCP measurements with solution-NMR order parameters from R-i relaxation and RDCs from a weakly oriented system for ubiquitin [138], because the solid-state order parameter is sensitive to motions that are on the submicrosecond scale, while the solution-NMR order parameter is sensitive to motions on the ps to ns time scale. Indeed, the solid-state NMR order parameter turns out to be generally smaller than the solution-NMR order parameter, and this inequality is easily rationalized by the difference in time scale. By contrast, many of the RDC-based order parameters are found to be very close to each other. 

Pico- to Nanosecond motions Conformationai Entropy and Aiiostery 

NMR relaxation experiments, however, show that the backbone flexi-bihty of mouse major urinary protein-I (MUP-I) increases upon binding the hydrophobic pheromone 2-5ec-butyl-4,5-dihydrothiazole [173]. The associated increase in backbone conformational entropy of the protein appears to make a substantial contribution towards stabilization of the protein-pheromone complex. To predict accurately the affinity of a protein for a given ligand, it is essential to have prior knowledge of both the enthalpy of binding, and the entropy of binding, ASt . To this end, the entro- 

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