Assembly Path of Multi-Metal Catalysis Clusters in [FeFe]-Hydrogenases Revealed


Complex enzymes containing iron-sulfur (Fe-S) clusters are ubiquitous in nature where they are involved in a number of reactions fundamental for life, including carbon dioxide and nitrogen fixation and hydrogen metabolism. Because these enzymes have high catalytic rates of hydrogen production, their potential for improving hydrogen–fuel cell technologies is the focus of much interest. One type of such enzymes, the [FeFe]-hydrogenases, is being investigated as an alternative biological catalyst to enzymes containing precious metals such as platinum. The active site of this hydrogenase, the H-cluster, has a [4Fe-4S] subcluster bridged to a 2Fe subcluster. Advancements in understanding how this H-cluster is synthesized in nature could contribute significantly to both the genetic engineering of hydrogen-producing microorganisms and the synthesis of biomimetic hydrogen-production catalysts. X-ray crystallography data from an intermediate, not-yet-mature form of [FeFe]-hydrogenase present insights into how the H-cluster (bio)synthesis occurs. This research was conducted at the Stanford Synchrotron Radiation Lightsource.


Mulder, D. W., et al. 2010. “Stepwise [FeFe]-Hydrogenase H-Cluster Assembly Revealed in the Structure of HydAΔEFG,” Nature 465, 248–51.