ABSTRACT
Hydrogenase catalyses the simplest redox-linked chemical reaction in Nature, so one might assume that the task of solving the puzzle of how hydrogenases actually do this is a simple one. As the chapters in this book describe, the scientists involved did not anticipate the peculiarities discovered in these ancient enzymes. As already described in the previous chapters, we now know of two classes of enzymes which, when in the pure state, can activate H2 without added cofactors.
