Model Promises Insights on Natural Catalysts

July 21, 2009
Researchers at the University of Illinois, Champaign, Ill., generated mock-ups of catalytic site.

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.

Model Effort

Figure 1. Research team includes Prof. Thomas Rauchfuss (center) and graduate students Bryan Barton (left) and Matthew Whaley.
Photo: L. Brian Stauffer, University of Illinois, Champaign.

“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.