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Updated: Feb 9, 2026

Isotopic Effect in Double Proton Transfer Process of Porphycene Investigated by Enhanced QM/MM Method
Published on: July 19, 2019
QM/MM calculations reveal a bridging hydroxo group in a vanadium nitrogenase crystal structure
Bardi Benediktsson1, Albert Th Thorhallsson, Ragnar Bjornsson
1Science Institute, University of Iceland, Dunhagi 3, 107 Reykjavik, Iceland.
Abstract:
A new 1.2 Å crystal structure of vanadium nitrogenase, isolated under turnover conditions, recently revealed a light atom ligand (OH or NH) replacing the bridging S2B sulfide of the FeV cofactor. QM/MM calculations on the new structure now reveal the light-atom ligand to be a bridging hydroxo group, probably derived from water binding to the cofactor.
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