On-the-fly' Kinetics of Enzymatic Racemization using Deuterium NMR in DNA-based Chiral Oriented Media.
Résumé
We report the first in situ and real-time monitoring of the interconversion of L- and D-alanine-d3 by alanine racemase from Bacillus Stearothermophilus directly observed by 2H-NMR spectroscopy in anisotropic phase. The enantiomers are distinguished by the difference of their 2H quadrupolar splittings in a chiral liquid-crystalline environment made of 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.