Ionic Coulomb blockade and the determinants of selectivity in the NaChBac bacterial sodium channel

Fedorenko, O. A.; Kaufman, I. Kh.; Gibby, William; Barabash, Miraslau L.; Luchinsky, D. G.; Roberts, Stephen A; McClintock, Peter V. E.

doi:10.1016/j.bbamem.2020.183301

Cited by 12 publications

(13 citation statements)

References 51 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In the selective regions jÁ K À Á Na j ) 0 species speci¯c conduction peaks are observed, maximizing under the conditions ÁG $ 0. Away from these peaks ionic Coulomb blockade occurs and the current is zero [11,29,34,39]. The blocking e®ect AMFE can be observed qualitatively: the orange curve represents the experimental data points.…”

Section: Application To Nachbac and Its Mutantmentioning

confidence: 96%

“…To compare the theory with experimental recordings and make predictions we consider two experiments. For further details of the experimental methods, including generation of mutant channels and their expression, as well as details of electrophysiological experiments, we refer to [11], and here we only present a concise summary. In the¯rst series of experiments we performed whole-cell current measurements through a NaChBac mutant (LDDWAD) channel, which we assume to have the same conduction mechanism as wild type NaChBac, in di®erent Na þ /K þ concentrations (AMFE experiment).…”

Section: Comparison With Experimentsmentioning

confidence: 99%

“…We observe a conduction peak, forming in the selective limits for either species. Peaks maximize under the condition that ÁG $ 0 i.e., a barrierless transition which is governed by ionic Coulomb blockade [11,29,34,39]. The orange curve represents the experimental data from LDDWAD exhibiting the blocking e®ect AMFE.…”

Section: Linear Responsementioning

confidence: 99%

“…The total selectivity (given by the sum over m) di®ers between adding the¯rst and second ions taking the values þ2:8 kT and þ5:6 kT , respectively, suggesting that it is harder for K þ to enter if Na þ is already occupying the pore. It is also likely that the conduction mechanism and number of binding sites will di®er in this mutant in addition to protonation e®ects [11]; and so further analysis will be required.…”

Section: Non-equilibrium Responsementioning

confidence: 99%

See 3 more Smart Citations

Theory and Experiments on Multi-Ion Permeation and Selectivity in the NaChBac Ion Channel

et al. 2019

View full text Add to dashboard Cite

The highly selective permeation of ions through biological ion channels is an unsolved problem of noise and fluctuations. In this paper, we motivate and introduce a non-equilibrium and self-consistent multi-species kinetic model, with the express aims of comparing with experimental recordings of current versus voltage and concentration and extracting important permeation parameters. For self-consistency, the behavior of the model at the two-state, i.e., selective limit in linear response, must agree with recent results derived from an equilibrium statistical theory. The kinetic model provides a good fit to data, including the key result of an anomalous mole fraction effect.

show abstract

Section: Application To Nachbac and Its Mutantmentioning

confidence: 96%

Section: Comparison With Experimentsmentioning

confidence: 99%

Section: Linear Responsementioning

confidence: 99%

Section: Non-equilibrium Responsementioning

confidence: 99%

See 2 more Smart Citations

Theory and Experiments on Multi-Ion Permeation and Selectivity in the NaChBac Ion Channel

et al. 2019

View full text Add to dashboard Cite

show abstract

“…The result is resonant barrier-less conduction for the favoured ionic species, very much in accord with what is seen experimentally. Generally, the ICB model predicts/explains well the phenomena of valence selectivity, including the famous divalent blockade of monovalent currents [15,21] in Ca 2+ channels, which has also been observed and investigated in the NaChBac channel and its mutants [22,23]. The ICB model was recently extended on the firm basis of very general statistical principles [24].…”

mentioning

confidence: 98%

A review of Handbook of Ion Channels, by Jie Zheng and Matthew C. Trudeau

McClintock

Kaufman

2018

Contemporary Physics

View full text Add to dashboard Cite

Finite velocity of ECG signal propagation: preliminary theory, results of a pilot experiment and consequences for medical diagnosis

Buchner

Zajdel

Pęczalski

et al. 2023

Sci Rep

View full text Add to dashboard Cite

A satisfactory model of the biopotentials propagating through the human body is essential for medical diagnostics, particularly for cardiovascular diseases. In our study, we develop the theory, that the propagation of biopotential of cardiac origin (ECG signal) may be treated as the propagation of low-frequency endogenous electromagnetic wave through the human body. We show that within this approach, the velocity of the ECG signal can be theoretically estimated, like for any other wave and physical medium, from the refraction index of the tissue in an appropriate frequency range. We confirm the theoretical predictions by the comparison with a direct measurement of the ECG signal propagation velocity and obtain mean velocity as low as v=1500 m/s. The results shed new light on our understanding of biopotential propagation through living tissue. This propagation depends on the frequency band of the signal and the transmittance of the tissue. This finding may improve the interpretation of the electric measurements, such as ECG and EEG when the frequency dependence of conductance and the phase shift introduced by the tissue is considered. We have shown, that the ECG propagation modifies the amplitude and phase of signal to a considerable extent. It may also improve the convergence of inverse problem in electrocardiographic imaging.

show abstract

Ionic Coulomb blockade and the determinants of selectivity in the NaChBac bacterial sodium channel

Cited by 12 publications

References 51 publications

Theory and Experiments on Multi-Ion Permeation and Selectivity in the NaChBac Ion Channel

Theory and Experiments on Multi-Ion Permeation and Selectivity in the NaChBac Ion Channel

A review of Handbook of Ion Channels, by Jie Zheng and Matthew C. Trudeau

Finite velocity of ECG signal propagation: preliminary theory, results of a pilot experiment and consequences for medical diagnosis

Contact Info

Product

Resources

About