About the Authors
Department of Microbiology and Immunology, University of California, San Francisco, San Francisco, California, United States of America
Department of Molecular Biology and Microbiology, Tufts University, Boston, Massachusetts, United States of America
The authors have declared that no competing interests exist.
The author(s) have made the following declarations about their contributions: Carried out the animal work in the initial GI tract screen: CAK. Conceived and designed the experiments: JCP CAK ADJ. Performed the experiments: JCP. Analyzed the data: JCP. Contributed reagents/materials/analysis tools: JCP CAK. Wrote the paper: JCP.