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Updated: Jun 21, 2026
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Membrane Transport Processes Analyzed by a Highly Parallel Nanopore Chip System at Single Protein Resolution
Published on: August 16, 2016
A membrane-reconstituted multisubunit functional proton pump on mesoporous silica particles.
Gustav Nordlund1, Jovice Boon Sing Ng, Lennart Bergström
1Department of Biochemistry and Biophysics, Centre for Biomembrane Research, Stockholm University, SE-10691 Stockholm, Sweden.
ACS Nano
|August 6, 2009
Summary
Researchers created a functional proteolipid membrane around silica particles, incorporating cytochrome c oxidase. This biofunctional interface supports membrane protein studies and drug delivery applications.
Area of Science:
- Biomaterials Science
- Nanotechnology
- Biophysics
Background:
- Mesoporous silica particles offer a versatile scaffold for biomimetic systems.
- Proteolipid membranes are crucial for cellular functions, including transport and energy transduction.
- Cytochrome c oxidase is a key enzyme in cellular respiration, catalyzing oxygen reduction and proton pumping.
Purpose of the Study:
- To construct and characterize a proteolipid membrane on mesoporous silica particles.
- To investigate the functionality and orientation of incorporated cytochrome c oxidase.
- To assess the potential of this system for bio-inspired applications.
Main Methods:
- Formation of proteolipid membranes on 550 nm mesoporous silica particles (3.0 nm pores).
- Incorporation of multisubunit cytochrome c oxidase into the membrane.
- Analysis of enzyme catalysis (O(2) reduction) and charge separation.
- Determination of cytochrome c oxidase orientation using spectroscopic methods.
- Proton gradient measurements to assess membrane integrity.
Main Results:
- Successful formation of a functional proteolipid membrane on silica particles.
- Cytochrome c oxidase exhibited catalytic activity and facilitated charge separation.
- Consistent enzyme orientation (approx. 70%) in supported membranes and lipid vesicles.
- Demonstrated proton impermeability, establishing a proton-tight system.
- Formation of a defined interior particle compartment separated from the external medium.
Conclusions:
- The silica-particle-supported proteomembrane is a functional and proton-tight bio-interface.
- The system mimics cellular compartmentalization and transport functions.
- This platform is suitable for studying membrane-bound proteins and for pharmaceutical drug delivery.
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