Crystal structure of HydF scaffold protein provides insights into [FeFe]-hydrogenase maturation.

ABSTRACT: [FeFe]-hydrogenases catalyze the reversible production of H2 in some bacteria and unicellular eukaryotes. These enzymes require ancillary proteins to assemble the unique active site H-cluster, a complex structure composed of a 2Fe center bridged to a [4Fe-4S] cubane. The first crystal structure of a key factor in the maturation process, HydF, has been determined at 3 ? resolution. The protein monomer present in the asymmetric unit of the crystal comprises three domains: a GTP-binding domain, a dimerization domain, and a metal cluster-binding domain, all characterized by similar folding motifs. Two monomers dimerize, giving rise to a stable dimer, held together mainly by the formation of a continuous ?-sheet comprising eight ?-strands from two monomers. Moreover, in the structure presented, two dimers aggregate to form a supramolecular organization that represents an inactivated form of the HydF maturase. The crystal structure of the latter furnishes several clues about the events necessary for cluster generation/transfer and provides an excellent model to begin elucidating the structure/function of HydF in [FeFe]-hydrogenase maturation.

SUBMITTER: Cendron L 

PROVIDER: S-EPMC3243517 | biostudies-literature | 2011 Dec

REPOSITORIES: biostudies-literature