1. Department of Chemistry and Biochemistry, Montana State University, Bozeman, Montana 59715, United States
2. Department of Pathology, Microbiology, and Immunology, Vanderbilt University Medical Center, Nashville, Tennessee 37232-2561, United States
3. Vanderbilt Institute for Infection, Immunology, and Inflammation, Vanderbilt University Medical Center, Nashville, Tennessee 37232, United States
4. Graduate Program in Microbiology and Immunology, Vanderbilt University, Nashville, Tennessee 37232, United States