title: Phototactic behaviour of the archaebacterial Natronobacterium pharaonis.
abstract: Natronobacterium pharaonis can react tactically to photo- and chemostimuli. It moves by rotation of a flagellar bundle which is monopolarly inserted. Under sufficient oxygen supply the photophobic response of N. pharaonis has been measured. The resulting action spectrum matches the absorption spectrum of the purified retinylidene protein psR-II. Retical synthesis could be inhibited by nicotine. Cells grown in the presence of nicotine show a strongly reduced photoresponse, which could be restored by addition of retinal. These data identify psR-II as the receptor for negative phototaxis.
authors.affiliation: Max-Planck-Institut für molekulaire Physiologie, Dortmund, Germany.
authors.forename: B
authors.initials: B
authors.lastname: Scharf
authors.forename: E K
authors.initials: EK
authors.lastname: Wolff
mesh_terms: D002633:Chemotaxis / Q000502:physiology*; D006216:Halobacteriaceae / Q000166:cytology* / Q000378:metabolism / Q000648:ultrastructure; D008027:Light; D008854:Microscopy, Electron; D012172:Retinaldehyde / Q000096:biosynthesis / Q000502:physiology
chemical_list: D012172:Retinaldehyde