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Updated: Nov 3, 2025
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Preparation of Polyoxometalate-based Photo-responsive Membranes for the Photo-activation of Manganese Oxide Catalysts
Published on: August 7, 2018
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Chromophore reduction plus reversible photobleaching: how the mKate2 "photoconversion" works
Elena A Protasova1, Alexander S Mishin2, Konstantin A Lukyanov2
1Faculty of Biology, Lomonosov Moscow State University, 119992, Moscow, Russia.
Summary
mKate2 protein exhibits non-canonical photoconversion, converting from red to green and blue spectral forms. This transformation is linked to chromophore photoreduction and photobleaching, with reversible changes upon reductant removal.
Area of Science:
- Biochemistry
- Biophysics
- Spectroscopy
Background:
- mKate red-to-green photoconversion is a poorly understood phototransformation in fluorescent proteins.
- The mechanism of this non-canonical phototransformation requires further investigation.
Purpose of the Study:
- To investigate the potential photoconvertibility of the mKate2 protein.
- To explore the connection between mKate2 photoconversion and its chromophore photoreduction.
Main Methods:
- Fluorescence microscopy
- Absorption spectroscopy
- Kinetics analysis
- Time-resolved fluorescence spectroscopy
- Photoconversion experiments with sodium dithionite
Main Results:
- Intense irradiation with sodium dithionite enhanced accumulation of green and blue spectral forms of mKate2.
- Short-wavelength spectral forms of mKate2 were present before photoactivation and increased light-independently after dithionite addition.
- The conversion process was facilitated by the photobleaching of the red chromophore form and was reversible upon reductant removal.
Conclusions:
- mKate2 protein demonstrates non-canonical photoconvertibility.
- The photoconversion mechanism involves chromophore photoreduction and photobleaching, influenced by reductant presence.
- Understanding mKate2 photoconversion provides insights into fluorescent protein photophysics.
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