title: DelPhiForce, a tool for electrostatic force calculations: Applications to macromolecular binding.
abstract: Long-range electrostatic forces play an important role in molecular biology, particularly in macromolecular interactions. However, calculating the electrostatic forces for irregularly shaped molecules immersed in water is a difficult task. Here, we report a new tool, DelPhiForce, which is a tool in the DelPhi package that calculates and visualizes the electrostatic forces in biomolecular systems. In parallel, the DelPhi algorithm for modeling electrostatic potential at user-defined positions has been enhanced to include triquadratic and tricubic interpolation methods. The tricubic interpolation method has been tested against analytical solutions and it has been demonstrated that the corresponding errors are negligibly small at resolution 4 grids/Å. The DelPhiForce is further applied in the study of forces acting between partners of three protein-protein complexes. It has been demonstrated that electrostatic forces play a dual role by steering binding partners (so that the partners recognize their native interfaces) and exerting an electrostatic torque (if the mutual orientations of the partners are not native-like). The output of DelPhiForce is in a format that VMD can read and visualize, and provides additional options for analysis of protein-protein binding. DelPhiForce is available for download from the DelPhi webpage at http://compbio.clemson.edu/downloadDir/delphiforce.tar.gz © 2017 Wiley Periodicals, Inc.
authors.affiliation: Department of Physics, Clemson University, Clemson, South Carolina, 29634.
authors.forename: Lin
authors.initials: L
authors.lastname: Li
authors.affiliation: Department of Physics, Clemson University, Clemson, South Carolina, 29634.
authors.forename: Arghya
authors.initials: A
authors.lastname: Chakravorty
authors.affiliation: Department of Physics, Clemson University, Clemson, South Carolina, 29634.
authors.forename: Emil
authors.initials: E
authors.lastname: Alexov
mesh_terms: D000465:Algorithms; D019295:Computational Biology / Q000379:methods; D003198:Computer Simulation; D008956:Models, Chemical; D011485:Protein Binding; D011506:Proteins / Q000737:chemistry*; D012984:Software; D055672:Static Electricity
chemical_list: D011506:Proteins
keywords: Poisson-Boltzmann equation; binding funnel; electrostatic force; electrostatic interactions; macromolecular binding