Researchers Wire Up Hydrogenase Enzymes

Researchers in Golden, Colorado, are reporting the first successful “wiring up” of hydrogenase enzymes. Those proteins are envisioned as potential stars in a future hydrogen economy where they may serve as catalysts for hydrogen production and oxidation in fuel cells.

Michael J. Heben, Paul W. King, and colleagues at the National Renewable Energy Laboratory (NREL) explain that bacterial enzymes called hydro-genases show promise as powerful catalysts for using hydrogen in fuel cells. But the scientists report dif-ficulty incorporating these enzymes into electrical devices because they don’t form good electrical connections with fuel cell components. Currently, precious metals are needed as catalysts.

The researchers combined hydrogenase enzymes with carbon nanotubes (pictured above), submicroscopic strands of pure carbon that are excellent electrical conductors. In laboratory studies, they demonstrated that a good electrical connection was established using photoluminescence spectroscopy measurements. These new “biohybrid” conjugates could reduce the cost of fuel cells by reducing or eliminating the need for platinum and other costly metal components, the researchers say.