Department of Microbiology, Cornell University, Ithaca, New York, United States of America.|Department of Microbiology, Cornell University, Ithaca, New York, United States of America.|Department of Microbiology, Cornell University, Ithaca, New York, United States of America.|Department of Microbiology, Cornell University, Ithaca, New York, United States of America.|Department of Microbiology, Cornell University, Ithaca, New York, United States of America.|Department of Microbiology, Cornell University, Ithaca, New York, United States of America.|Department of Microbiology, Cornell University, Ithaca, New York, United States of America.|Department of Microbiology, Cornell University, Ithaca, New York, United States of America.