Enzyme Active Sites (IMAGE) National Institutes of Natural Sciences Caption Figure 1. Structure of the active sites in [NiFe]-hydrogenase, [FeFe]-hydrogenase, and [Fe]-hydrogenase Credit NINS/IMS Usage Restrictions None License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.