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Engineering cytochromes for photocatalysis: Biohybrid assemblies for light-driven dye decoloration
Jessica H van Wonderen1, Daisy L Kent1, Mary E G Emmerson1
1School of Chemistry and School of Biological Sciences, University of East Anglia, Norwich Research Park, Norwich NR4 7TJ, UK.
New Biotechnology
|July 2, 2026
Summary
Biohybrid assemblies using MtrC enzyme and a ruthenium photosensitizer efficiently reduce azo dyes. This approach stores photoenergized electrons on heme cofactors, offering a sustainable alternative to titanium dioxide photocatalysts.
Area of Science:
- Bioinorganic Chemistry
- Photocatalysis
- Biotechnology
Background:
- Developing efficient photocatalysts requires coupling one-electron photochemistry with multi-electron chemical transformations.
- Titanium dioxide (TiO2) is a common photocatalyst, but its production and disposal have environmental and energy impacts.
Purpose of the Study:
- To create biohybrid assemblies for efficient photocatalysis by storing photoenergized electrons on enzyme cofactors.
- To demonstrate the use of MtrC enzyme-based biohybrids as a sustainable alternative to TiO2 for azo dye reduction.
Main Methods:
- Site-selective labeling of the MtrC enzyme with a Ruthenium(II) tris(bipyridine) (Ru(II)(bpy)3) photosensitizer dye.
- Irradiation of the biohybrid assemblies in the presence of a sacrificial electron donor to drive photocatalytic azo dye reduction.
Main Results:
- The Ru(II)(bpy)3-MtrC biohybrid assemblies effectively catalyzed azo dye reduction and decoloration.
- Photoenergized electrons were stored on MtrC's heme cofactors, analogous to electron storage in TiO2's conduction band.
Conclusions:
- MtrC-based biohybrid assemblies offer a novel and sustainable platform for photocatalysis.
- Future decoration with electrocatalysts could enable these assemblies to drive diverse light-driven reductive transformations, presenting an eco-friendly alternative to TiO2.
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