Charge state of the fast gate in chloride channels: insights from electrostatic calculations in a schematic model.
نویسندگان
چکیده
Fast gating is a unique property of chloride channels, where a permeating Cl(-) ion acts as its own ligand in opening the channel. The glutamate residue implicated in fast gating normally carries a unit negative charge. Whether this charge needs to be protonated to enable permeation of a Cl(-) ion is an important question that will affect how models of chloride channels are constructed. We investigate the energetic consequences of the charge state of this glutamate residue from continuum electrostatics using a schematic cylindrical channel model. Both analytical solutions of the Poisson equation for an infinite cylinder and numerical ones for a finite cylinder are employed in the calculations.
منابع مشابه
Electrostatic Control and Chloride Regulation of the Fast Gating of ClC-0 Chloride Channels
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ورودعنوان ژورنال:
- The Journal of chemical physics
دوره 127 19 شماره
صفحات -
تاریخ انتشار 2007