Analysis of the magnetic properties of nitrogenase FeMo cofactor by single-crystal EPR spectroscopy.

08.08.2013

Spatzal T, Einsle O, Andrade SL.

Angew Chem Int Ed Engl. 2013;52(38):10116-9

Angew Chem Int Ed Engl.         online article

The catalytic center of nitrogenase, the [Mo:7Fe:9S:C]:homocitrate FeMo cofactor, is a S = 3/2 system with a rhombic magnetic g tensor. Single-crystal EPR spectroscopy in combination X-ray diffraction were used to determine the relative orientation of the g tensor with respect to the cluster structure. The protein environment influences the electronic structure of the FeMo cofactor, dictating preferred orientations of possible functional relevance.