Prions in E. Coli, NIAID (IMAGE) University of California - San Diego Caption Prion proteins expressed in E. coli bacteria. Credit Image courtesy of NIAID. Usage Restrictions Use photo credit as indicated License Licensed 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.