Electrochemical processes bacteriorhodopsin membranes

Electrochemical Processes in Membranes That Contain Bacteriorhodopsin... 

There is now abundant evidenee that bacteriorhodopsin is a light-activated vectorial ion pump that translocates protons across the bacterial plasma membrane. The mechanism of proton translocation is unknown, although the process is linked to a complex photocycle that involves a number of intermediates [Mowery and Stoeckenius (1981) and Stoeckenius and Bogomolni (1982) see also articles in Packer (1982)] in which the Schiff base is protonated in the BR 570 state and deprotonated in the MR 412 state (Lewis et al., 1974 Aton et al., 1977 Rothschild et al., 1981). The electrochemical gradient generated in this way is used by the cell for ATP synthesis. 

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