SEARCH Articles Figures Tables Active sulfur Hydrogenase Hydrogenase active site Hydrogenase and Hydrogenase nickel-iron Hydrogenases active sites Hydrogenases nickel Iron activation Iron active Iron hydrogenase and Iron-sulfur Nickel activity Nickel-Iron-Sulfur Active Sites Nickel-Iron-Sulfur Active Sites Hydrogenase and CO Dehydrogenase Nickel-iron hydrogenases Sulfur nickel