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Accumulation and separation of membrane-bound proteins using hydrodynamic forces
Peter Jönsson1, Anders Gunnarsson, Fredrik Höök
1Department of Applied Physics, Chalmers University of Technology, SE-41296 Gothenburg, Sweden. jopeter@chalmers.se
Analytical Chemistry
|December 16, 2010
Summary
Hydrodynamic forces can now separate and accumulate membrane proteins in their native state. This novel method distinguishes proteins like streptavidin and cholera toxin by their unique movement, revealing molecular subpopulations.
Area of Science:
- Biotechnology
- Cell Biology
- Biophysics
Background:
- Separating membrane-bound proteins is a significant challenge in bioscience.
- Existing methods often alter protein structure or function.
Purpose of the Study:
- To demonstrate the use of hydrodynamic forces for accumulating and separating membrane-bound proteins.
- To investigate the potential for distinguishing protein subpopulations based on their movement characteristics.
Main Methods:
- Utilizing a microfluidic channel with a supported lipid bilayer (SLB).
- Employing hydrodynamic forces to manipulate streptavidin (SA) and cholera toxin (CT) anchored to the SLB.
- Reversing fluid flow to separate accumulated proteins based on characteristic drift velocities.
Main Results:
- Hydrodynamic forces successfully accumulated SA and CT proteins at the SLB edge.
- SA and CT were separated into distinct monomolecular populations despite similar molecular weights.
- Heterogeneity within cholera toxin molecules was identified, revealing three subpopulations with different drift velocities.
Conclusions:
- Hydrodynamic force manipulation offers a novel, non-disruptive method for membrane protein separation and accumulation.
- The technique allows for the characterization of protein subpopulations and molecular interactions within lipid bilayers.
- This approach holds promise for advancing bioscience and biotechnology research involving membrane proteins.
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