Mechanistic and physiological implications of the interplay among iron-sulfur clusters in [FeFe]-hydrogenases. A QM/MM perspective.

Mechanistic and Physiological Implications of the Interplay among Iron-Sulfur Clusters

Functional studies of [FeFe] hydrogenase maturation in an Escherichia coli biosynthetic system.

Maturation of [FeFe] hydrogenases requires the biosynthesis and insertion of the catalytic iron-sulfur cluster, the H cluster. Two radical S-adenosylmethionine (SAM) proteins proposed to function in H cluster biosynthesis, HydEF and HydG, were recently identified in the hydEF-1 mutant of the green alga Chlamydomonas reinhardtii (M. C. Posewitz, P. W. King, S. L. Smolinski, L. Zhang, M. Seibert,...

A look into the “H-Cluster” of FeFe-Hydrogenase through spectroscopic and synthetic methods

Since iron-sulfur clusters exist in our oxidizing environment, it can be concluded that at one time in our evolutionary history that the environment was instead a reducing environment. Iron-sulfur clusters which contain high spin Fe(II) and Fe(III) tetracoordinated metals can help facilitate electron-transfer processes, nitrogen fixation, catalytic sites in hydrogenases, and oxidation of NADH t...

The Physiological Functions and Structural Determinants of Catalytic Bias in the [FeFe]-Hydrogenases CpI and CpII of Clostridium pasteurianum Strain W5

The first generation of biochemical studies of complex, iron-sulfur-cluster-containing [FeFe]-hydrogenases and Mo-nitrogenase were carried out on enzymes purified from Clostridium pasteurianum (strain W5). Previous studies suggested that two distinct [FeFe]-hydrogenases are expressed differentially under nitrogen-fixing and non-nitrogen-fixing conditions. As a result, the first characterized [F...

The crystal structure of [Fe]-hydrogenase reveals the geometry of the active site.

Biological formation and consumption of molecular hydrogen (H2) are catalyzed by hydrogenases, of which three phylogenetically unrelated types are known: [NiFe]-hydrogenases, [FeFe]-hydrogenases, and [Fe]-hydrogenase. We present a crystal structure of [Fe]-hydrogenase at 1.75 angstrom resolution, showing a mononuclear iron coordinated by the sulfur of cysteine 176, two carbon monoxide (CO) mole...