1. Protein Expression Laboratory, National Institute of Arthritis and Musculoskeletal and Skin Diseases, National Institutes of Health, Bethesda, United States
2. Department of Microbiology and Immunology, Virginia Commonwealth University, Richmond, United States
3. Department of Microbiology, University of Alabama, Birmingham, United States
4. Direct Electron, San Diego, United States
5. Biological Science Imaging Resource, Florida State University, Tallahassee, United States