2f4k
|
Chicken villin subdomain HP-35, K65(NLE), N68H, K70(NLE), PH9
OverviewOverview
We have investigated the structure, equilibria, and folding kinetics of an, engineered 35-residue subdomain of the chicken villin headpiece, an, ultrafast-folding protein. Substitution of two buried lysine residues by, norleucine residues stabilizes the protein by 1 kcal/mol and increases the, folding rate sixfold, as measured by nanosecond laser T-jump. The folding, rate at 300 K is (0.7 micros)(-1) with little or no temperature, dependence, making this protein the first sub-microsecond folder, with a, rate only twofold slower than the theoretically predicted speed limit., Using the 70 ns process to obtain the effective diffusion coefficient, the, free energy barrier height is estimated from Kramers theory to be less, than approximately 1 kcal/mol. X-ray crystallographic determination at 1A, resolution shows no significant change in structure compared to the, single-norleucine-substituted molecule and suggests that the increased, stability is electrostatic in origin. The ultrafast folding rate, very, accurate X-ray structure, and small size make this engineered villin, subdomain an ideal system for simulation by atomistic molecular dynamics, with explicit solvent.
About this StructureAbout this Structure
2F4K is a Single protein structure of sequence from [1]. Full crystallographic information is available from OCA.
ReferenceReference
Sub-microsecond protein folding., Kubelka J, Chiu TK, Davies DR, Eaton WA, Hofrichter J, J Mol Biol. 2006 Jun 9;359(3):546-53. Epub 2006 Mar 31. PMID:16643946
Page seeded by OCA on Tue Jan 29 19:27:20 2008