Tube-Shaped Structure (IMAGE) Purdue University Caption Researchers have discovered a tube-shaped structure that forms temporarily in a certain type of virus to deliver its DNA during the infection process and then dissolves after its job is completed. The virus is pictured here infecting an E. coli cell. The tube attaches to the cell's inner and outer membranes, bridging the "periplasmic space" in between. A publication-quality graphic is available at http://www.purdue.edu/uns/images/2013/rossmann-tail.jpg. Credit (Purdue University image/Lei Sun) 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.