Tuning Catalytic Bias of Hydrogen Gas Producing Hydrogenases

Year: 2019

Type: article

Abstract: Hydrogenases display a wide range of catalytic rates and biases in reversible hydrogen gas oxidation catalysis. The interactions of the iron–sulfur-containing catalytic site with the local protein environment are thought to contribute to differences in catalytic reactivity, but this has not been demonstrated. The microbe Clostridium pasteurianum produces three [FeFe]-hydrogenases that differ in “catalytic bias” by exerting a disproportionate rate acceleration in one direction or the other that spans a remarkable 6 orders of magnitude. The combination of high-resolution structural work, biochemical analyses, and computational modeling indicates that protein secondary interactions directly influence the relative stabilization/destabilization of different oxidation states of the active site metal cluster. This selective stabilization or destabilization of oxidation states can preferentially promote hydrogen oxidation or proton reduction and represents a simple yet elegant model by which a protein catalytic site can confer catalytic bias.

Source: Journal of the American Chemical Society

DOI: 10.1021/jacs.9b08756

Institutions: National Laboratory of the Rockies, Washington State University, Montana State University, SLAC National Accelerator Laboratory, Stanford Synchrotron Radiation Lightsource, Arizona State University, Pacific Northwest National Laboratory, University of Georgia

Language: English

Topic: Metalloenzymes and iron-sulfur proteins

Subfield: Renewable Energy, Sustainability and the Environment

Field: Energy

Domain: Physical Sciences

Open Access status: green

Funders: U.S. Department of Energy, National Institutes of Health, Office of Science, National Institute of General Medical Sciences, Basic Energy Sciences, Biological and Environmental Research, SLAC National Accelerator Laboratory

OpenAlex ID: W2996537490