title: Carboxyl groups and the proton pump of bacteriorhodopsin.
mesh_terms: D001436:Bacteriorhodopsins / Q000378:metabolism*; D002338:Carotenoids / Q000378:metabolism*; D055598:Chemical Phenomena; D002627:Chemistry, Physical; D004578:Electron Spin Resonance Spectroscopy; D006217:Halobacterium; D011522:Protons; D013329:Structure-Activity Relationship
chemical_list: D011522:Protons; D002338:Carotenoids; D001436:Bacteriorhodopsins