Deprotonation of D96 in Bacteriorhodopsin Opens the Proton Uptake Pathway
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چکیده
منابع مشابه
Deprotonation of D96 in bacteriorhodopsin opens the proton uptake pathway.
Despite extensive investigation, the precise mechanism controlling the opening of the cytoplasmic proton uptake pathway in bacteriorhodopsin (bR) has remained a mystery. From an analysis of the X-ray structure of the D96G/F171C/F219L triple mutant of bR and 60 independent molecular dynamics simulations of bR photointermediates, we report that the deprotonation of D96, a key residue in proton tr...
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The removal of 75% of the lipid from bacteriorhodopsin caused the following: (i) decreased efficiency and rate of deprotonation of the protonated Schiff base (as monitored by absorption of the M412 intermediate); (ii) increased efficiency of deprotonation of deionized samples; (iii) a decrease by 1 unit in the pH at which deprotonation ceases; (iv) increased intensity of Eu3+ emission in Eu3+-r...
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The application of an external electric field to dry films of Asp-85-->Asn mutant bacteriorhodopsin causes deprotonation of the Schiff base, resulting in a shift of the optical absorption maximum from 600 nm to 400 nm. This is in marked contrast to the case of wild-type bacteriorhodopsin films, in which electric fields produce a red-shifted product whose optical properties are similar to those ...
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The kinetics and stoi~hiometry of lint-indu~d proton release in purple membrane sus~nsions have been investigated using the pH-indicator dye pyranine and sin~5tu~over flash spectroscopy at a time resolution of 0.1 ps. The number of protons detected by pyranine is inversely proportional to the buffehng power of the medium and 1.1 f 0.2 protons are released per photocycling bacteriorhodopsin mole...
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ژورنال
عنوان ژورنال: Structure
سال: 2013
ISSN: 0969-2126
DOI: 10.1016/j.str.2012.12.018