Erica Larson, Ph.D. (IMAGE) University of Pittsburgh Caption Dr. Erica Larson, research assistant professor in the University of Pittsburgh Department of Microbiology and Molecular Genetics Credit University of Pittsburgh Usage Restrictions Only for use in reporting on this study License Original content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.