1. Department of Chemistry, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213, United States
2. Department of Biochemistry, Molecular Biology
and Biophysics and Center for Metals in Biocatalysis, University of Minnesota, Minneapolis, Minnesota 55455, United States
3. Stanford Synchrotron Radiation Lightsource, 2575 Sand Hill Road, Menlo Park, California 94025, United States