Watery Passage (IMAGE) Rockefeller University Caption The pump, a single-molecule machine, (yellow coils) carries proteins through the cell membrane (pink and dark blue). Within the pump, the researchers found a strikingly large water-filled channel (light blue), a natural environment for hydrophilic proteins. Credit Laboratory of Membrane Biology and Biophysics/The Rockefeller University Usage Restrictions This image may be used only to illustrate the research described in the accompanying release. 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.