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. 1972 Jul;69(7):1723–1726. doi: 10.1073/pnas.69.7.1723

On the Theory of Ion Transport Across the Nerve Membrane, VI. Free Energy and Activation Free Energies of Conformational Change*

Terrell L Hill 1, Yi-Der Chen 1
PMCID: PMC426787  PMID: 4505649

Abstract

Empirical functions, such as n∞(V) and τn(V) (of the Hodgkin-Huxley type), can be recast in terms of more fundamental functions F(V) (related to a conformational free energy change) and θ(V) (related to the corresponding free energies of activation). Examples of F(V) and θ(V) are given, for squid and frog node. F(V) is essentially a quadratic function of V. The possible molecular origin, for protein-like subunits, of the linear (e.g., net charge) and quadratic (e.g., polarizability) terms in F(V) is discussed. The F(V), θ(V) kind of analysis leads rather automatically to a simple explanation of the well-known approximate coincidence in location (V value) of the maximum in τn(V) (time constant) and the steeply rising part of n∞(V) (also m, 1 - h).

Keywords: protein complex, electric field, net charge, polarizability, time constant maximum

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Selected References

These references are in PubMed. This may not be the complete list of references from this article.

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