Mechanistic insights into (bio)catalysts from unpaired electrons

Unpaired electrons play an important role in numerous redox-driven catalytic processes. Controlling their location and exploiting the interactions with their environment can provide key mechanistic information into these catalytic reactions. In this talk Dr. Roessler will discuss how her research group is exploiting and developing EPR-based techniques in conjunction with biochemistry, electrochemistry and materials chemistry to gain mechanistic insights into metalloenzymes and electron-transfer based catalytic reactions more generally.

Roessler will showcase how pulse EPR is helping to understand the proton-coupled electron transfer mechanism in respiratory complex I and then introduce film-electrochemical EPR spectroscopy (FE‑EPR) as a new tool to investigate surface-bound molecular catalysts, including enzymes. With operando FE-EPR we can monitor the evolution of radicals during catalysis in real time, providing a novel way to benchmark small-molecule electrocatalysts. Our current work is focussed on extending FE‑EPR to metalloenzymes and membrane proteins.