Theoretical and Computational Chemistry and Biophysical Chemistry
Ph.D., Weizmann Institute of Science (1979); M.Sc., Novosibirsk State University (1972); Fellow of the American Physical Society, (elected 1995)
Our group uses ideas and methods from theoretical physical chemistry to describe structural and dynamical properties of biological membranes and their interactions with proteins and peptides. Of special interest to us are interactions with antimicrobial peptides (AMPs). Natural AMPs represent first line of defense of eukaryotic cells against invading bacteria and they act by destroying bacterial membranes. In addition, a great number of AMPs have been shown to have anti-viral and anti-cancer properties. Although scientists are aware of the existence of antimicrobial peptides for more than thirty years, we are still lacking fundamental knowledge about mechanisms of their action. Our goal is to gain this knowledge. Understanding the mechanisms of action is also necessary, if we want to use natural AMPs, or synthetic ones as antibiotics or anti-cancer drugs. In our studies we use computer simulations techniques, such as molecular dynamics. Due to very complicated nature of the problem we need to use both detailed description of the system and also coarse-grained description and switch from one description to another during our simulations.
We also study interactions of other peptides, such as A-beta peptides with lipids in the membrane. It is known that Alzheimer's disease is connected to an aggregation disorder, with A-beta peptide being one of the main aggregating species. However, it is unknown what initiates this aggregation. Experimental evidence has shown that A-beta peptides will undergo a conformational change to an aggregate structure when interacting with surfaces of certain lipid membranes. It is of interest to our group to understand what causes this conformational change and what properties of lipids most promote this effect.