University of
Notre Dame
College of
Science
Department of
Physics

 

Colloquium

 

Picking up good vibrations -- Mechanical oscillations of viral capsids and their excitation with lasers.

 

 

Regents' Professor Otto F. Sankey
Arizona State University


Wednesday, September 2, 2009   4:00 p.m.  NSH 118

(Refreshments at 3:30 p.m. NSH 202)

 

Viruses are the simplest “life” form. These parasites reproduce by borrowing the machinery of their host cell. Many are pathogenic to plants, animals, and humans. Viruses possess an outer protein coat (capsid) that protects its genomic material that resides inside. We have developed a theoretical technique to model the very low frequency mechanical modes of the viral capsid with atomic resolution. The method uses empirical force fields and a mathematical framework borrowed from electronic structure theory for finding energy states. The low frequency modes can be “pinged” with an ultra-short laser pulse and the aim of the light/vibrational coupling is to interfere with the viral life cycle. The theoretical work here is motivated by the recent work of Tsen et al. [2] who have used ultra-short pulsed laser scattering to inactivate viruses.  Coupled mechanical oscillation of other floppy biomolecules such as a complete ATP binding cassette (ABC transporter) will also be discussed.

Co-authors of this work are Dr. Eric Dykeman, Prof. Frank Tsen and Daryn Benson.
[1] E.C. Dykeman et al., Phys. Rev. Lett. 100, 028101 (2008).
[2] K-T. Tsen, et al.,  J. of Physics – Cond. Mat. 19, 472201 (2007).


Host: Morten Eskildsen

All interested persons are cordially invited to attend.