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A Photoregulated Racemase Mimic
Monochura Saha1, Munshi Sahid Hossain1, Subhajit Bandyopadhyay1
1Department of Chemical Sciences, Indian Institute of Science Education and Research (IISER) Kolkata, Mohanpur, Nadia, West Bengal, 741246, India.
Angewandte Chemie (International Ed. in English)
|November 12, 2020
Summary
Researchers developed a light-controlled racemase enzyme system. This innovation allows precise control over the conversion of L-amino acids to D-amino acids using a photoswitchable pyridoxal phosphate (PLP) coenzyme.
Area of Science:
- Biochemistry
- Enzymology
- Photochemistry
Background:
- Racemase enzymes catalyze the interconversion of L-amino acids to their D-isomers.
- This process is crucial in various biological pathways and synthetic chemistry.
- The reaction mechanism involves a pyridoxal phosphate (PLP) coenzyme facilitating deprotonation-reprotonation steps.
Purpose of the Study:
- To engineer a novel racemase system with external light control.
- To investigate the influence of spatial arrangement on catalytic activity.
- To establish a photoswitchable platform for amino acid isomerization.
Main Methods:
- Construction of a PLP-photoswitch-imidazole triad.
- Modulation of the distance between a basic residue and the catalytic center.
- Spectroscopic and kinetic analyses to monitor racemization.
- Light irradiation to trigger conformational changes and control activity.
Main Results:
- Demonstration of light-dependent control over racemase activity.
- Correlation between the distance of the basic residue and reaction rate.
- Successful light-induced switching of L- to D-amino acid conversion.
- The triad system exhibits tunable catalytic properties based on light stimuli.
Conclusions:
- A photoswitchable racemase system was successfully developed.
- Light can effectively modulate the activity of PLP-dependent enzymes.
- This work provides a foundation for light-controlled biocatalysis and synthetic biology applications.
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