An investigation of hydrogenase I and hydrogenase II from Clostridium pasteurianum by resonance Raman spectroscopy. Evidence for a [2Fe-2S] cluster in hydrogenase I.

Resonance Raman spectra are reported for hydrogenase I and II from Clostridium pasteurianum. These spectra show overlapping bands with contributions from [4Fe-4S] clusters, known to be present in these enzymes, and from novel FeS centers of hitherto undefined structure. For hydrogenase I there are strong bands at 288 and 394 cm-1, which are seen in [2Fe-2S] proteins and in no other FeS species so far examined.