Biophysical Chemistry and Molecular Biophysics aim to understand how biological systems work in terms of the fundamental laws of Physics and Chemistry. Biomolecules, such as proteins and nucleic acids, usually have well defined conformations which often change in the course of their function. Our goal is to understand the forces that operate within and between biomolecules and develop quantitative mathematical models for their energy as a function of conformation. Such models are useful in many ways, such as predicting the three-dimensional structure from sequence, characterizing conformational changes involved in biological function, or predicting the binding affinity between two biomolecules.
One of the most difficult interactions to model is that between biomolecules and solvent. A simple analytical function that gives the solvation free energy for an arbitrary conformation would be highly desirable. Several years ago we developed a model (EEF1) based on the idea that solute atoms exclude solvent from the region they occupy. More recently we extended this model to biological membranes, which are essentially a heterogeneous solvent. This has allowed a much more efficient study of the interaction of peptides and soluble proteins with membranes, a process that is implicated in many biological processes such as membrane fusion, innate immunity, or signal transduction.