Department of Microbiology and Immunology, University of Michigan Medical School, Ann Arbor, Michigan, United States of America.|Department of Microbiology and Molecular Genetics, University of Pittsburgh, Pittsburgh, Pennsylvania, United States of America.|Department of Microbiology and Immunology, University of Michigan Medical School, Ann Arbor, Michigan, United States of America.|Robert H. Smith School of Business, University of Maryland, College Park, Maryland, United States of America.|Department of Microbiology and Immunology, University of Michigan Medical School, Ann Arbor, Michigan, United States of America.|Department of Pediatrics, Childrens Hospital of the University of Pittsburgh of UPMC, Pittsburgh, Pennsylvania, United States of America.|Department of Chemical Engineering, University of Michigan, Ann Arbor, Michigan, United States of America.|Department of Microbiology and Molecular Genetics, University of Pittsburgh, Pittsburgh, Pennsylvania, United States of America.|Department of Microbiology and Immunology, University of Michigan Medical School, Ann Arbor, Michigan, United States of America.