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Concentration-Temperature Superposition of Helix Folding Rates in Gelatin

J. L. Gornall·E. M. Terentjev
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Abstract

We study the kinetics of helix-coil transition in water solutions of gelatin (collagen protein) by optical rotation techniques combined with thermal characterization. By examining the rates of secondary helix folding, and covering a very wide range of solution concentrations, we are able to identify a universal exponential dependence of folding rate on concentration and quench temperature. We demonstrate a new concentration-temperature superposition of data at all temperatures and concentrations, and build the corresponding master curve. The results support the concept of a diffuse helix-coil transition. We find no concentration dependance of the normalized rate constant, suggesting first order (single) kinetics of secondary helix folding dominate in the early stages of renaturation.

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J. L. Gornall, E. M. Terentjev. 2006-03-05. Concentration-Temperature Superposition of Helix Folding Rates in Gelatin. https://doi.org/10.1103/physrevlett.99.028304

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