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Updated: Jun 26, 2026
08:09
A Micro-agar Salt Bridge Electrode for Analyzing the Proton Turnover Rate of Recombinant Membrane Proteins
Published on: January 7, 2019
Lateral proton transfer between the membrane and a membrane protein.
Linda Ojemyr1, Tor Sandén, Jerker Widengren
1Department of Biochemistry and Biophysics, The Arrhenius Laboratories for Natural Sciences, Stockholm University, Sweden.
Biochemistry
|January 27, 2009
Summary
Biological membranes accelerate proton transport. Incorporating cytochrome c oxidase into vesicles significantly enhanced proton transfer rates, showing membranes aid proton uptake by transporters.
Area of Science:
- Biochemistry
- Membrane Biology
- Bioenergetics
Background:
- Proton transport across biological membranes is crucial for energy conservation.
- The role of the membrane itself in facilitating proton transfer is under investigation.
Purpose of the Study:
- To investigate the effect of incorporating a proton transporter, cytochrome c oxidase, into a membrane on protonation kinetics.
- To determine how membrane incorporation influences proton transfer rates to a surface-attached probe.
Main Methods:
- Utilizing a fluorescent pH-sensitive probe attached to cytochrome c oxidase.
- Measuring protonation kinetics of the probe in solution and within phospholipid vesicles.
Main Results:
- Proton transfer to the probe was slightly accelerated when attached to the protein surface.
- Incorporation into phospholipid vesicles increased proton transfer rates by over 400-fold.
- This indicates rapid protonic contact between the probe and the membrane surface.
Conclusions:
- Biological membranes significantly accelerate proton uptake by membrane-bound proton transporters.
- The membrane environment plays a critical role in enhancing the efficiency of proton transport machinery.
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