The preparation and spectroscopic characterization of a CO-inhibited [FeFe] hydrogenase with a selectively 57Fe-labeled binuclear subsite is described. The precursor [57Fe2(adt)(CN)2(CO)4]2- was synthesized from the 57Fe metal, S8, CO, (NEt4)CN, NH4Cl, and CH2O. (Et4N)2[57Fe2(adt)(CN)2(CO)4] was then used for the maturation of the [FeFe] hydrogenase HydA1 from Chlamydomonas reinhardtii, to yield the enzyme selectively labeled at the [2Fe]H subcluster. Complementary 57Fe enrichment of the [4Fe-4S]H cluster was realized by reconstitution with 57FeCl3 and Na2S. The Hox-CO state of [257Fe]H and [457Fe-4S]H HydA1 was characterized by Mössbauer, HYSCORE, ENDOR, and nuclear resonance vibrational spectroscopy. (Chemical Equation Presented).
ASJC Scopus subject areas
- Colloid and Surface Chemistry