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Updated: May 10, 2026

Submillisecond Conformational Changes in Proteins Resolved by Photothermal Beam Deflection
Published on: February 18, 2014
Identification of two-step chemical mechanisms and determination of thermokinetic parameters using frequency
1Université Pierre et Marie Curie-Paris 6, Laboratoire de Physique Théorique de la Matière Condensée, UMR 7600 LPTMC, 4 place Jussieu, case courrier 121, 75252 Paris cedex 05, France.
Abstract:
Increased focus on kinetic signatures in biology, coupled with the lack of simple tools for chemical dynamics characterization, lead us to develop an efficient method for mechanism identification. A small thermal modulation is used to reveal chemical dynamics, which makes the technique compatible with in cellulo imaging. Then, the detection of concentration oscillations in an appropriate frequency range followed by a judicious analytical treatment of the data is sufficient to determine the number of chemical characteristic times, the reaction mechanism, and the full set of associated rate constants and enthalpies of reaction. To illustrate the scope of the method, dimeric protein folding is chosen as a biologically relevant example of nonlinear mechanism with one or two characteristic times.
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