A new method for computing the macromolecular electric potential.

R J Zauhar; R S Morgan

doi:10.1016/0022-2836(85)90399-7

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A new method for computing the macromolecular electric potential.

R J Zauhar·R S Morgan

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Abstract

A general methodology is developed for the rigorous computation of the electrostatic potential for a protein of arbitrary shape, assuming the presence of linear dielectric media. The theory proceeds by considering the distribution of induced polarization charge at the dielectric interface, rather than by attempting a direct solution of Poisson's equation (as in the finite-difference approach of Warwicker & Watson). The method is applied to a study of two-dimensional model proteins, where it is shown that the presence of a cleft is associated with a region of relatively high potential in the solvent medium. The results of a preliminary calculation in three dimensions for the protein lysozyme are also discussed; again, a region of enhanced potential is observed near the cleft at the active site. Our computational evidence supports the suggestion of Warwicker & Watson that clefts are associated with important electrostatic effects.

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R J Zauhar, R S Morgan. 1985-12-20. A new method for computing the macromolecular electric potential.. https://doi.org/10.1016/0022-2836(85)90399-7

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