Bernard Chasan

Education: AB, Columbia University; PhD, Cornell University

Field of Research: Molecular Biophysics

Research Statement:

My research (in loose collaboration with Professors El-Batanouny and Willis and with Horacio Cantiello of Massachusetts General Hospital) is concerned with the molecule ACTIN, which is part of the mammalian muscle apparatus, but is also involved in a huge range of cellular motions. Preliminary results from far infrared spectra suggest the presence of structural water in actin fibers; we speculate that this polymer is held together by water mediated hydrogen bonds between the monomer units. Further work to study this is planned, including Raman spectroscopy. We are also in the early stages of atomic force microscopy studies of this fascinating molecule, including the conditions under which the fibers form biologically important bundles, the polymerization process itself, and its behavior in various solution environments.

Image of an Actin protein filament, demonstrating the helical pitch of the macromolecule's quaternary structure.  *Click on image for full view*	Image of two actin filaments laid side by side.  As seen in the image, interaction between the two fibers is clearly observable.  *Click on image for full view*
Both images were obtained with a Digital Instruments™ Dimension 3000 Atomic Force Microscope in tapping mode, while the actin was polymerized in a biological buffer.