Effect of Xenon Binding to a Hydrophobic Cavity on the Proton Pumping Cycle in Bacteriorhodopsin

Crystal Structures of Different Substates of Bacteriorhodopsin's M Intermediate at Various pH Levels

“…Several researchers have previously proposed that this proton transfer process is mediated by a water cluster in which three or four water molecules are aligned. 25,41,42 If this mechanism works, we can suppose that, during the formation of N, a few water molecules move from the cytoplasmic medium to the hydrophobic cavities near the Schiff base.…”

Structure of archaerhodopsin-2 at 1.8 Å resolution

“…Transient transmission data from aR2 in claret membranes were acquired using a frequency-doubled Nd-YAG laser as described previously (Hayakawa et al, 2008). The absorption kinetics measured at various wavelengths were analyzed using the singular value decomposition method (Chizhov et al, 1996).…”

Crystal Structure of the Light-Driven Chloride Pump Halorhodopsin from Natronomonas pharaonis

“…Recent studies of the M → N transition of BR have suggested that the proton transfer from Asp96 to the deprotonated Schiff base takes place along a chain cluster of water molecules that is transiently formed when the inter-helical cavity is widened. [50][51][52] By contrast, it was reported that HR is converted to a light-driven proton pump when the chloride ion in the primary binding site is replaced by an inorganic base, azide. [53][54][55] [There was controversial discussion about the effect of azide on the functionality of HR, which may be dependent on whether shR or phR is investigated.…”