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Updated: Jul 13, 2026

Unraveling Entropic Rate Acceleration Induced by Solvent Dynamics in Membrane Enzymes
Published on: January 16, 2016
Lack of dynamics in the MabA active site kills the enzyme activity: practical consequences for drug-design studies
Guillaume Poncet-Montange1, Stephanie Ducasse-Cabanot, Annaick Quemard
1CNRS UMR5048, Centre de Biochimie Structurale, F-34090 Montpellier, France.
Abstract:
The MabA protein from Mycobacterium tuberculosis is a validated drug target. Previous structural studies of this protein showed dynamic behaviour in the catalytic site and described motion between an open 'active' holo form (with NADP) and a closed 'inactive' apo form (without NADP). Here, a mutation (G139A) is reported that leads to complete protein inactivation and freezes the catalytic site into its closed form, even in the presence of the cofactor. This observation suggests a new way to develop anti-MabA drugs via protein stabilization of the 'inactive' form.
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