NJIT Physics Department Seminar

October 13th, 2014, Monday

Modeling Protein-Membrane Interactions and Pore Formation

Prof. Themis Lazaridis

The City College of New York

(Biophysics, Host: Dias)

Time: 11:45am-12:45pm with 11:30am tea time

Room: ECE 202

Abstract:

Biological membranes consist of a lipid bilayer forming a hydrophobic barrier to uncontrolled ion movement. Protein-membrane interactions are involved in numerous biological processes. Over the past decade we developed a simplified approach for modeling such interactions in which lipid molecules and water are taken into account implicitly, via a solvation free energy term in the energy function. The membrane surface charge is modeled by use of the Gouy-Chapman theory. The transmembrane voltage, the dipole potential, and lateral pressure effects have also been incorporated into the model. An overview of the applications of this approach to biological problems such as transmembrane helix association or protein adsorption will be given. Of particular interest to us is the process of pore formation, which is involved in protein translocation, antibacterial action, cytotoxicity, and apoptosis. We developed an implicit model for aqueous membrane pores and used it to obtain insights into the mechanism of action of antimicrobial peptides. At the same time, all-atom explicit molecular dynamics simulations of peptides in lipid bilayers have provided an atomically detailed view of peptide-stabilized pores.