This Article Full Text Full Text (PDF) All Versions of this Article: biophysj.104.052548v1 88/6/3762    most recent Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via Google Scholar Google Scholar Articles by Plotkin, S. S. Search for Related Content PubMed PubMed Citation Articles by Plotkin, S. S.

Determination of Barrier Heights and Prefactors from Protein Folding Rate Data

Department of Physics and Astronomy, University of British Columbia, Vancouver, British Columbia, Canada

Correspondence: Address reprint requests to S. S. Plotkin, E-mail: steve{at}physics.ubc.ca.

We determine both barrier heights and prefactors for protein folding by applying constraints determined from experimental rate measurements to a Kramers theory for folding rate. The theoretical values are required to match the experimental values at two conditions of temperature and denaturant that induce the same stability. Several expressions for the prefactor in the Kramers rate equation are examined: a random energy approximation, a correlated energy approximation, and an approximation using a single Arrhenius activation energy. Barriers and prefactors are generally found to be large as a result of implementing this recipe, i.e., the folding landscape is cooperative and smooth. Interestingly, a prefactor with a single Arrhenius activation energy admits no formal solution.