Revealing the Molecular Underpinnings of a Key Enzyme

The Science

As a major component of the biological nitrogen cycle, the bacterial enzyme nitrogenase (N2ase) converts nitrogen from air into ammonia, thereby making it accessible to plant life. The enzyme achieves this feat at a metal-sulfur cluster called the FeMo cofactor by a mechanism that still is not wellunderstood. Research to better understand how metals and metal clusters interact with nitrogen and reduced nitrogen species is exploiting the soft X-ray region via transition metal L-edge and nitrogen K-edge spectroscopy. Complementary studies have used the stopped-flow infrared system in the mezzanine spectroscopy suite at the Advanced Light Source at Lawrence Berkeley National Laboratory to probe time-dependent binding of the carbon monoxide molecule CO to N2ase.

BER Program Manager

Amy Swain

U.S. Department of Energy, Biological and Environmental Research (SC-33)
Biological Systems Science Division
[email protected]


Yang, Z.-Y., L. C. Seefeldt, D. R. Dean, S. P. Cramer, and S. J. George. 2011. “Steric Control of the Hi-CO MoFe Nitrogenase Complex Revealed by Stopped-Flow Infrared Spectroscopy,” Angewandte Chemie International Edition 50, 272–75.