Protein folding kinetics: barrier effects in chemical and thermal denaturation experiments.

ABSTRACT: Recent experimental work on fast protein folding brings about an intriguing paradox. Microsecond-folding proteins are supposed to fold near or at the folding speed limit (downhill folding), but yet their folding behavior seems to comply with classical two-state analyses, which imply the crossing of high free energy barriers. However, close inspection of chemical and thermal denaturation kinetic experiments in fast-folding proteins reveals systematic deviations from two-state behavior. Using a simple one-dimensional free energy surface approach we find that such deviations are indeed diagnostic of marginal folding barriers. Furthermore, the quantitative analysis of available fast-kinetic data indicates that many microsecond-folding proteins fold downhill in native conditions. All of these p

SUBMITTER: Naganathan AN 

PROVIDER: S-EPMC2527040 | biostudies-literature | 2007 May

REPOSITORIES: biostudies-literature