<i>E. coli</i> Bacterium (IMAGE) Indiana University Caption The rod-shaped bacterium E. coli served as the model system for DNA repair in the study. Credit US Department of Defense Usage Restrictions None 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.