Proton-Coupled Electron Transfer Dynamics in the Catalytic Mechanism of a [NiFe]-Hydrogenase

What is it about?

The research described in this publication addresses the role of individual electron and proton transfer steps, and whether these processes may be coupled in the catalytic mechanism of a [NiFe]-Hydrogenase. This was achieved by photo-reduction of the enzyme on a rapid timescale (between 100ns and 1ms) and directly probing the active site by nanosecond time resolved infrared spectroscopy.

Featured Image

Why is it important?

This work demonstrates that proton and electron transfer to the active site are coupled during the active site transformation involving formation of the nickel-iron bridged hydride, but the two steps are separated in the subsequent transition necessary to generate the hydrogen forming state. Furthermore, this work experimentally validated numerous previously proposed catalytic intermediates from the labs of Lubitz, Albracht, Fontecilla-Camps and others as being kinetically competent.