Direct Observation of an Iron-Bound Terminal Hydride in [FeFe]-Hydrogenase by Nuclear Resonance Vibrational Spectroscopy.

ABSTRACT: [FeFe]-hydrogenases catalyze the reversible reduction of protons to molecular hydrogen with extremely high efficiency. The active site ("H-cluster") consists of a [4Fe-4S]_H cluster linked through a bridging cysteine to a [2Fe]_H subsite coordinated by CN^- and CO ligands featuring a dithiol-amine moiety that serves as proton shuttle between the protein proton channel and the catalytic distal iron site (Fe_d). Although there is broad consensus that an iron-bound terminal hydride species must occur in the catalytic mechanism, such a species has never been directly observed experimentally. Here, we present FTIR and nuclear resonance vibrational spectroscopy (NRVS) experiments in conjunction with density functional theory (DFT) calculations on an [FeFe]

SUBMITTER: Reijerse EJ 

PROVIDER: S-EPMC5545132 | biostudies-literature | 2017 Mar

REPOSITORIES: biostudies-literature