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Updated: May 26, 2026
10:03
Proton Transfer and Protein Conformation Dynamics in Photosensitive Proteins by Time-resolved Step-scan Fourier-transform Infrared Spectroscopy
Published on: June 27, 2014
Molecular scale conductance photoswitching in engineered bacteriorhodopsin
Olivia Berthoumieu1, Amol V Patil, Wang Xi
1Department of Biochemistry, University of Oxford, South Parks Road, Oxford OX1 3QU, United Kingdom.
Nano Letters
|December 14, 2011
Summary
Bacteriorhodopsin (BR), a light-driven proton pump, was anchored to gold electrodes. This protein
Area of Science:
- Biophysics
- Nanotechnology
- Biochemistry
Background:
- Bacteriorhodopsin (BR) is a light-driven proton pump from Halobacterium salinarium.
- BR retains photoactivity in dry states, showing nanotechnological potential.
Purpose of the Study:
- To anchor BR asymmetrically onto gold electrodes via cysteine mutation.
- To investigate the electronic properties and stability of immobilized BR trimers.
Main Methods:
- Covalent anchoring of modified BR onto gold electrodes.
- Characterization using surface plasmon resonance, voltammetry, ellipsometry, and atomic force microscopy (AFM).
- Conducting AFM to probe conductance of isolated BR trimers.
Main Results:
- Successful chemisorption of BR onto gold electrodes.
- Reproducible and reversible switching of BR trimer conductance under illumination and dark conditions.
- Demonstrated surface stability of BR for nanodevice applications.
Conclusions:
- Immobilized BR exhibits light-dependent conductance switching.
- This demonstrates BR's potential for use in nanodevices.
- The engineered BR shows promise for stable, light-responsive electronic components.
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