Events in proton pumping by bacteriorhodopsin
نویسندگان
چکیده
منابع مشابه
A correlation between proton pumping and the bacteriorhodopsin photocycle.
In an attempt to establish a relationship between proton pumping and the photocycle intermediates of bacteriorhodopsin, we have studied the effects of pH and temperature on flash-induced proton pumping and the photointermediates O640 and M412. The relative quantum yield of flash-induced proton pumping is both pH and temperature dependent. It is high in the acid pH range and at low temperatures ...
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The light-driven proton pump bacteriorhodopsin (BR) from Halobacterium salinarum is tightly regulated by the [H(+)] gradient and transmembrane potential. BR exhibits optoelectric properties, since spectral changes during the photocycle are kinetically controlled by voltage, which predestines BR for optical storage or processing devices. BR mutants with prolonged lifetime of the blue-shifted M i...
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The parallel model for the bacteriorhodopsin (BR) photocycle at neutral pH and a temperature near 20 degrees C contains an M-fast cycle with steps BR-->K-->L-->Mf-->N-->O-->BR and an M-slow cycle which contains steps BR-->K-->L-->Ms-->BR. With increasing actinic laser strength, the M-fast cycle at first rises faster than the M-slow cycle, but reaches saturation sooner and at a lower level than ...
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Stephen Waschuk et al. report that the fungus Leptosphaeria maculans possesses a rhodopsin protein able to translocate protons across membranes in response to light, a function thought to be unique to prokaryotes. Traditionally, respiration and chlorophyll-based photosynthesis are the two methods used by eukaryotes to create a proton gradient, whereas archaebacteria undergo retinal-based photos...
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ژورنال
عنوان ژورنال: Biophysical Journal
سال: 1983
ISSN: 0006-3495
DOI: 10.1016/s0006-3495(83)84413-0