Subsecond Proton-Hole Propagation in Bacteriorhodopsin
نویسندگان
چکیده
منابع مشابه
Mechanism of primary proton transfer in bacteriorhodopsin.
Recent structures of putative intermediates in the bacteriorhodopsin photocycle have provided valuable snapshots of the mechanism by which protons are pumped across the membrane. However, key steps remain highly controversial, particularly the proton transfer occurring immediately after retinal trans-->cis photoisomerization. The gradual release of stored energy is inherently nonequilibrium: wh...
متن کاملDeprotonation 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...
متن کاملProton transfer pathways in bacteriorhodopsin at 2.3 angstrom resolution.
Photoisomerization of the retinal of bacteriorhodopsin initiates a cyclic reaction in which a proton is translocated across the membrane. Studies of this protein promise a better understanding of how ion pumps function. Together with a large amount of spectroscopic and mutational data, the atomic structure of bacteriorhodopsin, determined in the last decade at increasing resolutions, has sugges...
متن کاملCalculation of proton transfers in Bacteriorhodopsin bR and M intermediates.
Residue ionization states were calculated in nine crystal structures of bacteriorhodopsin trapped in bR, early M, and late M states by multiconformation continuum electrostatics. This combines continuum electrostatics and molecular mechanics, deriving equilibrium distributions of ionization states and polar residue and water positions. The three central cluster groups [retinal Schiff base (SB),...
متن کاملStructural and energetic determinants of primary proton transfer in bacteriorhodopsin.
In the light-driven bacteriorhodopsin proton pump, the first proton transfer step is from the retinal Schiff base to a nearby carboxylate group. The mechanism of this transfer step is highly controversial, in particular whether a direct proton jump is allowed. Here, we review the structural and energetic determinants of the direct proton transfer path computed by using a combined quantum mechan...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
ژورنال
عنوان ژورنال: Biophysical Journal
سال: 2003
ISSN: 0006-3495
DOI: 10.1016/s0006-3495(03)74887-5