A molecular machine for pumping protons (IMAGE) DOE/SLAC National Accelerator Laboratory Caption An animation shows a proton pump called V-ATPase at work. These pumps are embedded in the membranes of cellular organelles, where they bring in protons that are essential for the organelle's function. The top part of the pump generates energy to drive the rotating part at the bottom, which is like a molecular Ferris wheel that picks up protons on the outside of the organelle and drops them off inside. Scientists at SLAC National Accelerator Laboratory, Stanford University, SUNY Upstate Medical University and Arizona State University used cryo-EM images and computer simulations to reveal key details about how the pump works. Credit From the labs of S.-H. Roh and S. Wilkens 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.