Physics of Selective Conduction and Point Mutation in Biological Ion Channels

2020/10/16 by W. A. T. Gibby, M. L. Barabash, Miraslau L. Barabash +4 · 12 citations
Biochemistry, Genetics and Molecular Biology · Chemistry · Physics and Astronomy · #Biology #Coulomb #Electron #Gene #Genetics #Ion #Ion channel #Ion channel regulation and function #Ionic bonding #KcsA potassium channel #Mass Spectrometry Techniques and Applications #Mutation #Physics #Quantum mechanics #Statistical physics #Thermal conduction #Thermodynamics #physics.bio-ph #thermodynamics and calorimetric analyses

paper · pdf · doi:10.1103/physrevlett.126.218102

published in Physical Review Letters 126(21), 218102 (American Physical Society)

arxiv created 2020/10/16 · openalex publication_date 2021/05/28 · arxiv updated 2021/06/02 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05

Abstract

We introduce a statistical and linear response theory of selective conduction in biological ion channels with multiple binding sites and possible point mutation. We derive an effective grand-canonical ensemble and generalized Einstein relations for the selectivity filter, assuming strongly coordinated ionic motion, and allowing for ionic Coulomb blockade. The theory agrees well with data from the KcsA K⁺ channel and a mutant. We show that the Eisenman relations for thermodynamic selectivity follow from the condition for fast conduction and find that maximum conduction requires the binding sites to be nearly identical.

Citations

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