Related Experiment Video
Updated: May 29, 2026

Anaerobic Protein Purification and Kinetic Analysis via Oxygen Electrode for Studying DesB Dioxygenase Activity and Inhibition
Published on: October 3, 2018
ONIOM(DFT:MM) study of 2-hydroxyethylphosphonate dioxygenase: what determines the destinies of different substrates?
1Division of Chemistry and Biological Chemistry, School of Physical and Mathematical Sciences, Nanyang Technological University, 21 Nanyang Link, Singapore 637371, Singapore. hirao@ntu.edu.sg
Abstract:
Why can enzymes provide different products from only slightly different substrates? While the reaction of 2-hydroxyethylphosphonate (2-HEP) catalyzed by 2-hydroxyethylphosphonate dioxygenase (HEPD) yields hydroxymethylphosphonate and formic acid, the HEPD-catalyzed reaction of 1-HEP gives acetylphosphate. ONIOM(DFT:MM) was used to uncover the distinct reaction mechanisms for the different substrates. Calculations show that, in both reactions, similar radical intermediates are generated by the same process. After the formation of common radical intermediates, proton-coupled electron transfer (PCET) operates in the 1-HEP reaction, whereas in the 2-HEP reaction, it cannot occur and an alternative pathway sets in. Thus, the PCET plays a critical role in defining the fates of the substrates.
More Related Videos
Related Concept Videos
Hydroboration-Oxidation of Alkenes
Regioselectivity and Stereochemistry of Hydroboration
Hydroboration proceeds in a concerted fashion with the attack of borane on the π bond, giving a cyclic four-centered transition state. The –BH2 group is bonded to the less substituted carbon and –H to the more substituted carbon. The concerted nature requires the simultaneous addition of –H and –BH2 across the same face of the alkene giving syn stereochemistry.
Regioselective Formation of Enolates
Oxidation of Alkenes: Syn Dihydroxylation with Osmium Tetraoxide
Regioselectivity and Stereochemistry of Acid-Catalyzed Hydration
Oxidation of Alkenes: Anti Dihydroxylation with Peroxy Acids

