Characterizing protein folding transition States using Psi-analysis.

Adarsh D Pandit; Bryan A Krantz; Robin S Dothager; Tobin R Sosnick

doi:10.1385/1-59745-189-4:83

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PubMed · 16957319

Characterizing protein folding transition States using Psi-analysis.

Adarsh D Pandit·Bryan A Krantz·Robin S Dothager·Tobin R Sosnick

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Abstract

We discuss the implementation of Psi-analysis for the structural characterization of protein folding transition states. In Psi-analysis, engineered bi-histidine metal ion binding sites are introduced at surface positions to stabilize secondary and tertiary structures. The addition of metal ions stabilizes the interaction between the two known histidines in a continuous fashion. Measuring the ratio of transition state stabilization to that of the native state provides information about the presence of the metal binding site in the transition state. Psi-Analysis uses noninvasive surface mutations and does not require specialized equipment, so it can be readily applied to characterize the folding of many proteins. As a result, this method can provide a wealth of high-resolution quantitative data for comparison with theoretical folding simulations. Additionally, investigations of other biological processes also may utilize metal binding sites and Psi-analysis to detect conformational events during catalysis, assembly, and function.

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Binding Sites Histidine Kinetics Metals Models, Molecular Protein Conformation Protein Engineering Protein Folding Proteins Comparative Study Journal Article Research Support, N.I.H., Extramural

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Adarsh D Pandit, Bryan A Krantz, Robin S Dothager, Tobin R Sosnick. 2007. Characterizing protein folding transition States using Psi-analysis.. https://doi.org/10.1385/1-59745-189-4%3A83

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