Ion Channel Electrostatics and the Shapes of Channel Proteins
The accelerating progress that is being made in channel reconstitution will eventually lead to the determination of protein structures, i.e., of channel shapes. These will surely not all be right circular cylinders, and a pore’s structure can affect ion passage through it in two ways. Short-range forces govern selectivity and the detailed nature of the potential energy profile for ion permeation. Long-range electrostatic forces control ion access to the channel, influence the relationship of apparent electrical distance to structure, and provide a slowly varying background potential, which modifies channel kinetics.
KeywordsChannel Protein Potential Profile Mouth Region Image Energy Double Occupancy
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