S1 Supporting information An organometallic complex formed by an unconventional radical SAM enzyme Min Dong, 1,# Masaki Horitani, 2,# Boris Dzikovski, 1 Maria-Eirini Pandelia 3 , Carsten Krebs 4 , Jack H. Freed, 1 Brian M. Hoffman 2, * and Hening Lin 1,5, * 1 Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York, 14853. 2 Department of Chemistry, Northwestern University, Evanston, Illinois 60208. 3 Department of Biochemistry, Brandeis University, MA 02453. 4 Department of Chemistry and Department of Biochemistry and Molecular Biology, The Pennsylvania State University, University Park, Pennsylvania 16802. 5 Howard Hughes Medical Institute, Cornell University, Ithaca, New York, 14853. A. Reagents and Methods S2-S9 B. Supplementary Figures S10-S32 C. References S33