The Journal of Biological Physics and Chemistry


Volume 4, Number 1, p. 7-10

R. Tóth-Boconádi and L. Keszthelyi

Institute of Biophysics, Biological Research Centre of the Hungarian Academy of Sciences, H-6701 Szeged, Hungary

Further evidence of photocurrent from the illuminated O-intermediate in the bacteriorhodopsin mutant L93A

Important details of the proton pumping mechanism may be obtained by optically exciting intermediates in the bacteriorhodopsin photocycle. In previous work it was found that the O-intermediate of the bacteriorhodopsin mutant L93A pumped protons. Here this result is confirmed with superposed quasi-continuous green and red light, demonstrating the parallel change of the current magnitude and the O population with increasing green illumination.

Keywords: orientation, proton translocation, purple membrane, quasi-continuous illumination

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