Electrostatics of nanosystems: Application to microtubules and the ribosome

Evaluation of the electrostatic properties of biomolecules has become a sta ndard practice in molecular biophysics. Foremost among the models used to e lucidate the electrostatic potential is the Poisson-Boltzmann equation; how ever, existing methods for solving this equation have limited the scope of accurate electrostatic calculations to relatively small biomolecular system s. Here we present the application of numerical methods to enable the trivi ally parallel solution of the Poisson-Boltzmann equation for supramolecular structures that are orders of magnitude larger in size. As a demonstration of this methodology, electrostatic potentials have been calculated for lar ge microtubule and ribosome structures. The results point to the likely rol e of electrostatics in a variety of activities of these structures.