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Updated: May 12, 2026

Real-time Observation of the DNA Strand Exchange Reaction Mediated by Rad51
Published on: February 13, 2019
"On-the-fly" kinetics of enzymatic racemization using deuterium NMR in DNA-based chiral oriented media
Monique Chan-Huot1, Philippe Lesot, Philippe Pelupessy
1Institut Curie, Centre de Recherche, 91405 Orsay Cedex, France. chanhuot.monique@gmail.com
Abstract:
We report the in situ and real-time monitoring of the interconversion of L- and D-alanine-d3 by alanine racemase from Bacillus stearothermophilus directly observed by (2)H NMR spectroscopy in anisotropic phase. The enantiomers are distinguished by the difference of their (2)H quadrupolar splittings in a chiral liquid crystal containing short DNA fragments. The proof-of-principle, the reliability, and the robustness of this new method is demonstrated by the determination of the turnover rates of the enzyme using the Michaelis-Menten model.
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