Picosecond dynamical changes on denaturation of yeast phosphoglycerate kinase revealed by quasielastic neutron scattering
✍ Scribed by Véronique Receveur; Patrick Calmettes; Jeremy C. Smith; Michel Desmadril; Gerrit Coddens; Dominique Durand
- Publisher
- John Wiley and Sons
- Year
- 1997
- Tongue
- English
- Weight
- 94 KB
- Volume
- 28
- Category
- Article
- ISSN
- 0887-3585
No coin nor oath required. For personal study only.
✦ Synopsis
Quasielastic neutron scattering experiments performed on yeast phosphoglycerate kinase in the native form and denatured in 1.5 M guanidinium chloride reveal a change in the fast (picosecond time scale) diffusive internal dynamics of the protein. The momentum and energy transfer dependences of the scattering for both states are fitted by an analytical model in which, on the experimentally accessible picosecond time scale and angstrom length scale, the dynamics of a fraction of the nonexchangeable hydrogens in the protein is described as a superposition of vibrations with uniform diffusion in a sphere, the rest of the hydrogens undergoing only vibrational motion. The fraction diffusing changes, from D60% in the native protein to D82% in the denatured protein. The radius of the sphere also changes slightly, from D1.8 Å in the native protein to D2.2 Å in the denatured protein. Possible implications of these results for the general protein folding problem are discussed.