Cell-free H-cluster synthesis and [FeFe] hydrogenase activation: all five CO and CN⁻ ligands derive from tyrosine.

ABSTRACT: [FeFe] hydrogenases are promising catalysts for producing hydrogen as a sustainable fuel and chemical feedstock, and they also serve as paradigms for biomimetic hydrogen-evolving compounds. Hydrogen formation is catalyzed by the H-cluster, a unique iron-based cofactor requiring three carbon monoxide (CO) and two cyanide (CN⁻) ligands as well as a dithiolate bridge. Three accessory proteins (HydE, HydF, and HydG) are presumably responsible for assembling and installing the H-cluster, yet their precise roles and the biosynthetic pathway have yet to be fully defined. In this report, we describe effective cell-free methods for investigating H-cluster synthesis and [FeFe] hydrogenase activation. Combining isotopic labeling with FTIR spectroscopy, we conclusively show that each of the CO and CN⁻

SUBMITTER: Kuchenreuther JM 

PROVIDER: S-EPMC3105041 | biostudies-literature | 2011

REPOSITORIES: biostudies-literature