Function
Bacteriorhodopsin (Br) is a membrane protein in Archaea which moves protons across the cell membrane. See also Bacteriorhodopsin (Hebrew).
Halorhodopsin uses light energy to pump chloride through biological membranes in Haloarchaea[1].
Sensory rhodopsin uses light energy to pump calcium ions through biological membranes. They are ubiquitous and use retinal as their chromophore[2].
Xanthorhodopsin is a light-driven proton pump which uses the carotenoid salinixanthin as a second chromophore[3].
Archaerhodopsin responds to yellow or green light by pumping protons out of cells and are used as optogenetic tools[4].
Proteorhodopsins are the most abundant retinal-based photoreceptors. It is found in many marine bacteria[5].
Deltarhodopsin is a light-driven proton pump found in the archaebacteria Halloterrigena turkmenica[6].
Xenorhodopsin is an enigmatic new class of microbial rhodopsins[7].
Structural highlights
Br is composed of 6 α-helical elements each containing a retinal molecule. The retinal changes its ground state conformation upon binding of a proton, causing the Br to change conformation to the activated state and pump the proton. [8] (Hydrophobic, Polar).
3D Structures of bacteriorhodopsin
Bacteriorhodopsin 3D structures