About the Authors

Narayanan Sathish

Affiliation Department of Microbiology, School of Dental Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, United States of America

Fan Xiu Zhu

Address Current address: Department of Biological Sciences, Florida State University, Tallahassee, Florida, United States of America

Affiliation Department of Microbiology, School of Dental Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, United States of America

Yan Yuan

yuan2@pobox.upenn.edu

Competing Interests

The authors have declared that no competing interests exist.

Author Contributions

Conceived and designed the experiments: YY. Performed the experiments: NS FXZ. Analyzed the data: NS YY. Contributed reagents/materials/analysis tools: FXZ. Wrote the paper: NS YY.