1. Department of Pharmacology and Cancer Biology; Duke University School of Medicine; Durham NC USA
2. Division of Infectious Diseases, Department of Medicine; Duke University School of Medicine; Durham NC USA
3. Department of Biochemistry and Biophysics; UCSF; San Francisco CA USA
4. Department of Genetics; Yale University School of Medicine; New Haven CT USA
5. Department of Molecular Genetics and Microbiology; Duke University School of Medicine; Durham NC USA
6. Department of Biochemistry; Duke University School of Medicine; Durham NC USA