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Updated: Sep 21, 2025
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
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Protein conformational changes and protonation dynamics probed by a single shot using quantum-cascade-laser-based IR
Luiz Schubert1, Pit Langner1, David Ehrenberg1
1Experimental Molecular Biophysics, Department of Physics, Freie Universität Berlin, Arnimallee 14, 14195 Berlin, Germany.
The Journal of Chemical Physics
|June 1, 2022
Summary
Quantum cascade laser (QCL)-based infrared spectroscopy enables label-free monitoring of protein reactions. This technique allows for single-shot experiments to track protein structural changes and proton movement in real-time.
Area of Science:
- Spectroscopy
- Biophysics
- Chemical Kinetics
Background:
- Mid-infrared (Mid-IR) spectroscopy is a label-free method for studying protein reactions.
- Protein conformational changes and protonation are critical to many biological processes.
Purpose of the Study:
- To investigate protein conformational changes and protonation events using quantum-cascade-laser-based dual-comb spectroscopy.
- To compare the efficacy of dual-comb spectroscopy with a tunable quantum cascade laser (QCL)-based scanning spectrometer for monitoring irreversible reactions.
Main Methods:
- Utilized quantum-cascade-laser-based dual-comb spectroscopy for single-shot experiments.
- Employed bacteriorhodopsin, a well-characterized membrane protein, as a model system.
- Compared dual-comb spectroscopy with a homebuilt tunable QCL-based scanning spectrometer.
Main Results:
- Demonstrated the feasibility of QCL-based infrared spectroscopy for tracing functionally relevant protein structural changes.
- Showcased the ability to monitor proton translocations via single-shot experiments.
- Achieved high time resolution in monitoring irreversible reactions.
Conclusions:
- QCL-based infrared spectroscopy is a viable tool for real-time monitoring of protein dynamics.
- The technique is suitable for studying the kinetics of irreversible reactions in biochemical transformations.
- Single-shot experiments offer a powerful approach for investigating rapid biological processes.
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