title: Isolation of photochemically active archaebacterial photoreceptor, pharaonis phoborhodopsin from Natronobacterium pharaonis.
abstract: A photoreceptor, pharaonis phoborhodopsin for the negative phototaxis of extremely halophilic and alkalophilic archaebacterium, Natronobacterium pharaonis was isolated in a photochemically active state. A detailed examination of the chromatographic separation made it possible to separate contaminating proteins, such as cytochromes. The procedure resulted in a 2938-fold enrichment with a yield of 15.5%. The isolated pharaonis phoborhodopsin had an absorption maximum at 498 nm, an A280/A498 ratio of 1.27 and a single band near 24 kDa on the SDS-polyacrylamide gels. The isolated pharaonis phoborhodopsin underwent a photochemical reaction after flash excitation. The photocyclic reaction closely resembled that of the membrane-bound pharaonis phoborhodopsin.
authors.affiliation: Institute of Physical and Chemical Research (RIKEN), Saitama, Japan.
authors.forename: H
authors.initials: H
authors.lastname: Tomioka
authors.forename: H
authors.initials: H
authors.lastname: Sasabe
mesh_terms: D001105:Archaea / Q000378:metabolism*; D019843:Archaeal Proteins; D001436:Bacteriorhodopsins / Q000737:chemistry / Q000302:isolation & purification* / Q000378:metabolism; D002338:Carotenoids; D002845:Chromatography; D002852:Chromatography, Ion Exchange; D017886:Durapatite; D004591:Electrophoresis, Polyacrylamide Gel; D025602:Halorhodopsins; D007700:Kinetics; D010777:Photochemistry; D025603:Sensory Rhodopsins; D013053:Spectrophotometry
chemical_list: D019843:Archaeal Proteins; D025602:Halorhodopsins; D025603:Sensory Rhodopsins; C061508:sensory rhodopsin II protein, archaeal; D002338:Carotenoids; D001436:Bacteriorhodopsins; D017886:Durapatite