Regensburg 2002 – wissenschaftliches Programm

Bereiche | Tage | Auswahl | Suche | Downloads | Hilfe

SYBM: Physik biologischer Materie

SYBM 401: Physics of biological matter: Poster

SYBM 401.44: Poster

Dienstag, 12. März 2002, 18:00–19:30, H37

Kinetics of a spontaneous binding and enforced unbinding of a biomembrane and a substrate whose mutual adhesion is mediated by specific interaction — •Alexei Boulbitch — Dept. fuer Biophysik E22, Technische Universitaet Muenchen, James-Franck-Str. 1, D-85747 Garching bei Muenchen

Spontaneous binding and enforced unbinding of a biomembrane and a substrate whose mutual adhesion is mediated by specific interaction are studied theoretically. The both processes take place via a motion of the adhesion rim. Equation of motion of the rim is deduced and use it to analyze (i) the spontaneous adhesion of the membrane onto the substrate and (ii) their enforced unbinding.

(i) Under small ligand (or receptor)concentration the spontaneous binding is dominated by their diffusion, while at high concentration one it is dominated by the kinetics of ligand- receptor binding.

(ii) The enforced unbinding of the membrane from a substrate is described motion. It is characterized by an initial phase of very slow rim motion followed by a rapid breakage of adhesion. We show that the unbinding force depends on the power of the rate of force application, the power being 1/2 at small and 1/3 at large force applied to membranes.

Experiments on the spontaneous membrane-substrate binding and enforced unbinding are discussed in the framework of the above approach.