Nature doesn’t rely on precious metals as catalysts for oxidation of hydrogen. Instead, it uses baser-metal-containing enzymes such as iron-iron hydrogenase and nickel-iron hydrogenase. Researchers at the University of Illinois, Champaign, Ill., recently modeled the active site in such an enzyme (Figure 1). Their model reportedly is the first to include a bridging hydride ligand, an essential component of the catalyst. They expect it to encourage development of biomimetric hydrides and lead to mechanistic insights about such natural catalysts.
“Nature relies on a very elaborate architecture to support its own ‘hydrogen economy.’ We cracked that design by generating mock-ups of the catalytic site to include the substrate hydrogen atom,” notes Thomas Rauchfuss, professor of chemistry. “By building a model that contains a hydride ligand, we have proven that the behavior of these natural catalysts can be understood and optimized,” explains Matthew Whaley, a graduate student involved in the project. “By better understanding the mechanism in the nickel-iron hydrogenase active site, we are learning how to develop new kinds of synthetic catalysts that may be useful in other applications,” adds graduate student Bryan Barton, lead author of a recent paper on the development in JACS Communications.