Molecular dynamics simulations of lipid membranes.

I'm currently interested in determining which molecular scale interactions govern the interesting structural and mechanical properties observed in the membranes of various cell types. I'm using molecular dynamics simulations to look at the permeability of brain endothelial cells, the response of red blood cells to oxidative stress, and the role of hyaluronic acid in synovial fluid.

The blood brain barrier (BBB) is responsible for maintaining the homeostatic microenvironment of the brain. It is thought that the lipid composition of the endothelial cells of the BBB plays an important role in preventing the passive diffusion of molecules across the barrier. Unfortunately, the BBB doesn't discriminate between harmful pathogens and pharmacological therapeutics: 99 % of all drugs developed by the pharmaceutical industry are unable to pass the BBB, which poses a huge challenge in the development of drugs to treat Alzheimer's disease. I've been using atomistic molecular dynamics simulations to study the structure, dynamics and permeability of a realistic model of a brain endothelial cell membrane.

Hyaluronaic acid (HA) is a high molecular weight polysaccharide that is of interest both as a component of biological scaffolds and as a biomarker for a number of diseases including cancer, asthma and arthritis. In synovial joints such as the knee, HA is thought to attach multilamellar lipid stacks the cartilage surface, with these lipid membranes providing lubrication when the joint is subjected to normal and shear forces. Presence of low molecular weight HA is associated with osteoarthritis, and may be the primary cause of the condition. In collaboration with Mateusz Sikora at the Max Planck Institute for Biophysical Chemistry, I have been developing a coarse-grained model of HA which I will then use to look at how the molecular weight of HA modulates its interactions with a model synovial fluid lipid membrane.