[A new approach to the electrostatic stabilization of cations in the aqueous cavity of K+ channel: the role of nonlocal-electrostatic effects].

Methods of nonlocal electrostatics, applied to ion channels in our previous papers, are used to analyze the stability of K+ in the aqueous cavity of K+ channel. Other authors used formulas of classical electrostatics to calculate the energy of K+ in the aqueous cavity of KcsA. Using a new formulation of nonlocal-electrostatic theory, we obtained a formula for the image force energy acting on K+, which is in the center of a spherical cavity of K+ channel. It is shown that nonlocal-electrostatic effects in the aqueous cavity of K+ channel leads to a decrease in the energy K+ on 4kT compared with the calculation by the formulas of classical electrostatics.