Reconstitution of an Iron-Only Hydrogenase

Abstract

Exts. from Clostridium pasteurianum were denatured in 7M urea anaerobically to eliminate hydrogenase activity. Hydrogenase from the denatured exts. could be renatured by incubation anaerobically with sulfide, reduced thiol reagents such as dithiothreitol, and Fe2+. Reconstituted exts. recovered 2% of the original H2 evolution activity. Reconstitution was also successful with purified hydrogenase I that was denatured anaerobically. This recovered 3.6% of its original H2 evolution activity. These results suggest that accessory proteins are not necessary for assembly of Fe-only hydrogenases as they are for Ni-Fe hydrogenases. [on SciFinder(R)]