Hydrogenases are enzymes of considerable interest for their potential biotechnological applications both as catalysts in biofuel cells and hydrogen producers. However, these applications can be greatly affected by their reactions with atmospheric oxygen. In order to better understand this problem, we have investigated a single mutation of the naturally O2-tolerant E. coli [NiFe] hydrogenase-1, which makes it O2-sensitive by changing its [4Fe-3S] cluster into a novel [4Fe-4S] cluster. Our theoretical study explains in detail the observed different redox properties of these two clusters and sheds considerable light on the biological solution to prevent O2-based deactivation.
X-ray structural, functional and computational studies of the O2-sensitive E. coli hydrogenase-1 C19G variant reveal an unusual [4Fe–4S] cluster. A. Volbeda, J. M. Mouesca, C. Darnault, M. M. Roessler, A. Parkin, F. A. Armstrong and J. C. Fontecilla-Camps. ChemComm; accepted 4th June 2018, DOI: 10.1039/c8cc02896f