Evaluation of protein electrostatic potential from molecular dynamics simulations in the presence of exogenous electric fields. The case study of myoglobin

When studying proteins in solution it is apparent that electrostatic interactions play a role in folding, conformational stability, and other chemical-physical properties. Electrostatics considers the evaluation of the static electrical field that is formed between charged species once a rearrangement of their charge distributions has occurred due to the influence of each other and their local environment. A powerful tool used to follow the many interactions among the polar and/or charged residues is computer simulations, which can provide atomic-scale information on energetic and dynamic contributions of the bio-molecular structure. Here we use molecular dynamics (MD) simulations to map on a three-dimensional space the electrostatic interactions within the protein itself and of the protein with its aqueous environment. The method has been first tested on a simulation domain of water molecules and then applied to the myoglobin-water system. The presence of intense electric fields has also been considered and some representative results are discussed.