2006

Abstract:
Our research focuses in the study of complex systems from a molecular level to understand and predict properties manifested at the macroscopic level. We apply a number of computational and theoretical methods to model molecular interactions of complex systems. In this talk, we will highlight our current efforts using molecular simulations to understand phospholipid bilayer and clathrate hydrate structures. Phospholipid bilayers are the main structure of cell membranes, and as such, they are essential in the protection of cells and in controlling biophysical and biochemical processes in and out of the cell. Although much is known about the physical-chemical properties of phospholipid bilayer structures, there are many important molecular properties that are still poorly understood, especially those related to the structure and dynamics of the phospholipids, and they how they are affected by physical and chemical changes. Here, we will describe our simulation studies to understand and quantify structural changes of phospholipid bilayers as a function of temperature, in particular the molecular properties as bilayers transition between the liquid-order (gel) and liquid-disorder (fluid) phases. We will also describe our recent findings on the stability of phospholipid bilayers in the presence of clathrate hydrate structures, which are crystalline inclusion compounds formed from a network of hydrogen bonded water molecules enclosing small compounds. The latter simulations are the first step toward applying clathrate hydrates in biological processes, such as in stabilization.