1. Cell Structure Laboratory, National Center for Biotechnology, Spanish National Research Council, Madrid, Spain
2. Department of Pathology, Microbiology, and Immunology, Vanderbilt University School of Medicine, Nashville, TN
3. Department of Pediatrics, University of Pittsburgh School of Medicine, Pittsburgh, PA
4. Department of Microbiology and Molecular Genetics, University of Pittsburgh School of Medicine, Pittsburgh, PA
5. Center for Microbial Pathogenesis, UPMC Children’s Hospital of Pittsburgh, Pittsburgh, PA
6. Department of Macromolecular Structures, National Center for Biotechnology, Spanish National Research Council, Madrid, Spain