1. Department of Pediatrics, Vanderbilt University School of Medicine, Nashville, Tennessee 37212, United States
2. Department of Pathology, Microbiology and Immunology, Vanderbilt University Medical Center, Nashville, Tennessee 37212, United States
3. Department of Medicine, Vanderbilt University School of Medicine, Nashville, Tennessee 37212, United States
4. Department of Chemistry, Vanderbilt University, Nashville, Tennessee 37235, United States
5. Department of Microbiology and Molecular Genetics, Michigan State University, East Lansing, Michigan 48823, United States
6. Department of Pediatrics, University of Washington, Seattle, Washington 98109, United States
7. Departments of Biochemistry and Chemistry, Vanderbilt University, Nashville, Tennessee 37235, United States
8. Department of Veterans Affairs, Tennessee Valley Healthcare Systems, Nashville, Tennessee 37212, United States