Tracking Surface Proteins (IMAGE) Indiana University Caption Outer membrane proteins of an Agrobacterium tumefaciens cell were labeled in red, with images taken every 50 minutes as the cell grew. In panels three and four it is clear that the cell on the left (red) has kept all the labeled proteins, whereas the other cell has all new surface proteins. Credit Image by Pamela J.B. Brown, Indiana University. 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.