PHYS 65 |
| Cell-cell adhesion in vivo is determined primarily by large numbers of protein binders on cell membranes. One fundamental question is how bond chemistry determines the strength of the intercellular junctions. In addition, while much is known about the physics determining strengths of single (isolated) noncovalent bonds, cell adhesion is rarely mediated by single proteins. However, no analyses have explored how molecular properties scale the collective adhesive behavior of multiple bonds in parallel between membrane surfaces. This talk describes a multi-scale investigation of the adhesive strength of multiple protein bonds in parallel and the correlation of the adhesion with the thermodynamic and kinetic properties of the bonds. Atomistic simulations identified critical load bearing amino acids at the protein-protein interfaces. Mutants generated on the basis of these simulations were characterized thermodynamically and kinetically. Subsequent molecular force measurements of protein-mediated intermembrane adhesion in turn established correlations between the thermodynamic and kinetic properties and the measured adhesion. These findings suggest surprising similarities between the strengths of single bonds and strength of adhesion mediated by multiple bonds in parallel. |
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Physical Chemical Foundations of Biological Membrane Phenomena
1:20 PM-5:00 PM, Sunday, 10 September 2006 Grand Hyatt San Francisco -- Merced, Oral
Division of Physical Chemistry |