Physics Department, The University of Memphis
MEMPHYS-Center for Biomembrane Physics, Univ. of Southern Denmark, Denmark
March 29th, 2006, 4:00pm, Manning Hall 201
Refreshments served at 3:30pm, Manning Hall 222
Biomembranes are quasi-two-dimensional, fluid, self-assembled structures composed
mainly of lipid molecules and a small amount of cholesterol and proteins, with energies
only tens of the thermal energy. They have unique structural and functional properties
that express the exquisite exactness of purpose reflective of natural evolution during
the last five billion years.
The primary roles that biomembranes play are (i) the separation between the inner
and outer environments of the cell (or organelles such the nucleus, Golgi apparatus,
and mitochondria), and (ii) the support of a complex molecular machinery important
for both a wide variety of biochemical functions and the structural integrity of the
cell. Nanoscale to micronscale mimetic lipid membranes in the form of vesicles (called
liposomes) are used as simplified models to understand biomembranes as well as in
many applications including drug delivery and cosmetics.
In this colloquium, after introducing the audience to the fascinating world of self-assemblies
and lipid membranes, I will discuss how a theoretical physicist using relatively simplified
models can contribute to the understanding of the mechanics, structure, stability
and heterogeneities of lipid membranes. In particular, I will discuss our recent proposal
regarding the stability of nanoscale lipid domains in biomembranes known as rafts.