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Updated: Dec 13, 2025

Monitoring the Reductive and Oxidative Half-Reactions of a Flavin-Dependent Monooxygenase using Stopped-Flow Spectrophotometry
Published on: March 18, 2012
Structural evidence for a reaction intermediate mimic in the active site of a sulfite dehydrogenase
Ahmed Djeghader1, Melanie Rossotti2, Saleh Abdulkarim1
1Department of Chemical Sciences and Bernal Institute, University of Limerick, Ireland. Tewfik.soulimane@ul.ie.
Abstract:
By combining X-ray crystallography, electron paramagnetic resonance techniques and density functional theory-based modelling, we provide evidence for a direct coordination of the product analogue, phosphate, to the molybdenum active site of a sulfite dehydrogenase. This interaction is mimicking the still experimentally uncharacterized reaction intermediate proposed to arise during the catalytic cycle of this class of enzymes. This work opens new perspectives for further deciphering the reaction mechanism of this nearly ubiquitous class of oxidoreductases.
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