The gating charge should not be estimated by fitting a two-state model to a Q-V curve

Authors

Francisco Bezanilla
Carlos A. Villalba-Galea, Virginia Commonwealth UniversityFollow

ORCiD

0000-0002-6489-4651

Document Type

Article

Publication Title

The Journal of General Physiology

ISSN

1540-7748

Volume

142

Issue

6

DOI

10.1085/jgp.201311056

First Page

575

Last Page

578

Publication Date

12-1-2013

Abstract

The voltage dependence of charges in voltage-sensitive proteins, typically displayed as charge versus voltage (Q-V) curves, is often quantified by fitting it to a simple two-state Boltzmann function. This procedure overlooks the fact that the fitted parameters, including the total charge, may be incorrect if the charge is moving in multiple steps. We present here the derivation of a general formulation for Q-V curves from multistate sequential models, including the case of infinite number of states. We demonstrate that the commonly used method to estimate the charge per molecule using a simple Boltzmann fit is not only inadequate, but in most cases, it underestimates the moving charge times the fraction of the field.

Comments

Authors retain copyright

Recommended Citation

Bezanilla, F., & Villalba-Galea, C. A. (2013). The gating charge should not be estimated by fitting a two-state model to a Q-V curve. The Journal of General Physiology, 142(6), 575–578. DOI: 10.1085/jgp.201311056
https://scholarlycommons.pacific.edu/phs-facarticles/317

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