Identification and Characterization of the “Super‐Reduced” State of the H‐Cluster in [FeFe] Hydrogenase: A New Building Block for the Catalytic Cycle?

Super-reduced and super-active: A new redox state in the active site of algal [FeFe] hydrogenases has been identified and characterized by EPR and FTIR spectroscopy. Electrochemical and in vitro essays show that this species is highly active in hydrogen production and suggest that it is a key intermediate in the catalytic cycle of all [FeFe] hydrogenases. Detailed facts of importance to specialist readers are published as ”Supporting Information”. Such documents are peer-reviewed, but not copy-edited or typeset. They are made available as submitted by the authors. Please note: The publisher is not responsible for the content or functionality of any supporting information supplied by the authors. Any queries (other than missing content) should be directed to the corresponding author for the article.