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Title: A Closer Look at the Isomerization of 5-Androstene-3,17-Dione to 4-Androstene-3,17-Dione in Ketosteroid Isomerase
We present a computational study of a substrate isomerization catalyzed by Ketosteroid Isomerase based on QM/MM calculations, our Unified Reaction Valley Approach and Local Vibrational Mode Analysis. In summary, our study quantifies Talaly’s postulate that the major role of the enzyme pocket is to shield the migrating hydrogen atom from interactions with solvent molecules. Our analysis further confirms that there is no exceptional hydrogen bonding between the substrate and surrounding enzyme amino acids, which could account for lowering the activation barrier.
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Journal of Computational Biophysics and Chemistry
Page Range or eLocation-ID:
313 to 333
Sponsoring Org:
National Science Foundation
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