BACTERIORHODOPSIN

The Uses of BACTERIORHODOPSIN

Bacteriorhodopsin from Halobacterium salinarum has been used:

• in generation of droplet lipid bilayer
• as a standard in quadrupole time-of-flight (QTOF) mass spectroscopy (MS)
• in the generation of protein-detergent complex and micelles for dynamic light scattering studies

Definition

bacteriorhodopsin: A membraneboundprotein of the halophilic (saltresistant)bacterium Halobacteriumhalobium. When activated by light, itpumps protons out of the cell; thiscreates a concentration gradient,which enables ATP to be synthesized.Bacteriorhodopsin is composed ofseven α-helix segments, which spanthe membrane and are joined togetherby short amino-acid chains. Itcontains the prosthetic group retinal,which is also found in the pigmentrhodopsin in the rod cells of vertebrates.

General Description

Bacteriorhodopsin (BR) is a covalent complex comprising bacterioopsin protein and retinal cofactor in the equimolar ratio. It corresponds to the molecular weight of 27kDa. BR belongs to the retinylidene class of proteins. It is a seven-membrane helical protein that acts as a photon-driven pump. BR can be used in studies of the folding and kenetics of β-helical proteins.

Biochem/physiol Actions

Bacteriorhodopsin (BR) from Halobacterium salinarum acts as a proton-driven pump. BR can be used in studies of the folding and kinetics of α-helical proteins. It is thermally stable and exhibits high photoelectric and photochemical efficiency. BR exists as trimer in a hexagonal lattice. Its photocycle intermediates are exploited in bioelectronics majorly in photoelectric and photochemical applications.