About the Authors

Charles Berry

Affiliation Department of Family and Preventive Medicine, School of Medicine, University of California San Diego, La Jolla, California, United States of America

Sridhar Hannenhalli

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

Jeremy Leipzig

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

Frederic D Bushman

To whom correspondence should be addressed. E-mail: bushman@mail.med.upenn.edu

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

Competing Interests

The authors have declared that no competing interests exist.

Author Contributions

CB, SH, JL, and FDB conceived and designed the experiments, performed the experiments, and analyzed the data. CB, SH, and JL contributed reagents/materials/analysis tools. CB and FDB wrote the paper.