You are currently viewing the summary.View Full Text
How does a protein pump protons in only one direction? In his Perspective, Gennis explains how this occurs in bacteriorhodopsin, a membrane protein that pumps protons in response to light stimulation. A new structure by Luecke et al. on p. 255 shows that small changes in the conformation within bacteriorhodopson induced as a result of light absorption by retinal, are sufficient to change the pK's of several key residues enough to promote the release of protons on one side of the membrane.