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Updated: Jul 16, 2026
09:35
Real Time Measurements of Membrane Protein:Receptor Interactions Using Surface Plasmon Resonance (SPR)
Published on: November 29, 2014
Impact of polymer tether length on multiple ligand-receptor bond formation
C Jeppesen1, J Y Wong, T L Kuhl
1Materials Research Laboratory, Department of Chemical Engineering, University of California, Santa Barbara, CA 93106, USA.
Science (New York, N.Y.)
|July 21, 2001
Summary
Cell adhesion efficiency relies on rare extended polymer chain conformations, not just molecular binding properties. This finding impacts understanding of cell interactions and biomaterials.
Area of Science:
- Biophysics
- Materials Science
- Cell Biology
Background:
- Cell adhesion is mediated by ligands on flexible tethers binding to surface receptors.
- Understanding the dynamics of these tethers is crucial for cell interaction studies.
Purpose of the Study:
- To quantify polymer chain dynamics and ligand-receptor binding kinetics.
- To determine the spatial range and efficiency of tethered ligand-receptor interactions.
Main Methods:
- Monte Carlo simulations
- Diffusion reaction theory
- Surface force measurements (biotin-streptavidin system)
Main Results:
- Polymer chain dynamics and binding kinetics were quantified.
- Binding efficiency depends critically on rare, extended polymer conformations.
- Molecular architecture and equilibrium tether configuration are less critical than rare conformations.
Conclusions:
- The "rare" extended conformations of polymer tethers are key to efficient cell adhesion.
- This provides new insights into the biophysics of molecular interactions at cell surfaces.
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