1. Department of Chemistry, Pennsylvania State University, University Park, Pennsylvania, USA
2. Department of Microbiology, University of Georgia, Athens, Georgia, USA
3. Department of Chemistry, Emory University, Atlanta, Georgia, USA
4. Molecular, Cellular and Integrative Biosciences Program, Pennsylvania State University, University Park, Pennsylvania, USA
5. Department of Biochemistry and Molecular Biology, Pennsylvania State University, University Park, Pennsylvania, USA