Interpretation of the Ussing flux ratio from the fluctuation theorem
| Autor: | Chi-Pan Hsieh |
|---|---|
| Rok vydání: | 2009 |
| Předmět: |
Potassium Channels
Chemistry Fluctuation theorem Entropy media_common.quotation_subject Organic Chemistry Mathematical analysis Biophysics Non-equilibrium thermodynamics Biological Transport Second law of thermodynamics Models Biological Biochemistry Ion Channels Flux ratio Green–Kubo relations Ion Diffusion Electrochemistry Thermodynamics Statistical physics Entropy (arrow of time) media_common |
| Zdroj: | Biophysical Chemistry. 139:57-62 |
| ISSN: | 0301-4622 |
| DOI: | 10.1016/j.bpc.2008.10.002 |
| Popis: | The fluctuation theorem gives a mathematical expression to quantify the probability of observing events violating the second law of thermodynamics in a small system over a short period of time. The theorem predicts the ratio of forward (entropy-producing) runs to the backward (entropy-consuming) runs for a nanometer-sized molecular machine in a nonequilibrium system. However, few experimental verifications of the theorem have been carried out. In this paper, I show that the Ussing flux ratio, the ratio of outward to inward unidirectional ion fluxes across a membrane channel, can be derived from the fluctuation theorem if we consider the ion channel and the contacting solutions as a small nonequilibrium system. The entropy change due to ion electrodiffusion is expressed from the fundamental equation for the entropy change. Thus, the empirical flux ratio equation can be interpreted from the more general fluctuation theorem, and serves as a verification of the theorem. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
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