Parts | Days | Selection | Search | Updates | Downloads | Help

BP: Fachverband Biologische Physik

BP 13: Posters: Biological Membranes

BP 13.4: Poster

Monday, March 14, 2011, 17:15–20:00, P3

Dynamics of specific adhesion — •Timo Bihr¹, Ana-Sunčana Smith², and Udo Seifert¹ — ¹II. Institut für Theoretische Physik, Uni Stuttgart — ²Institut für Theoretische Physik and Excellence Cluster: Engineering of Advanced Materials, Universität Erlangen-Nürnberg

We perform dynamic Langevin simulations of a membrane specifically adhering to the substrate. The membrane is modeled by a Hamiltonian that apart from the Helfrich term contains a harmonic contribution accounting for the nonspecific membrane-substrate potential and a term associated with the formation of ligand-receptor bonds. During the simulation the receptors are immobilized on the substrate, whereas the ligands diffuse freely through the membrane. Ligand-receptor binding and unbinding is modeled by time-dependent rate constants that satisfy detailed balance.

We find that when the correlations between the bonds are weak, sparse arrangement of bonds are observed and the increase of the number of bonds in time is associated with a squeezed exponential. When the correlations between the bonds are strong, a domain grows radially out of a nucleation center. In the reaction limited regime, this behavior is analytically modeled and the results compare well to those arising from several experimental studies.