The reaction centre of the photounit of Rhodospirillum rubrum is anchored to the light-harvesting complex with four-fold rotational disorder

Article Article scientifique Article The reaction centre of the photounit of Rhodospirillum rubrum is anchored to the light-harvesting complex with four-fold rotational disorder eng 1998 author Stahlberg Henning author Dubochet Jacques 50368 author Vogel Horst 742418 author Ghosh Robin 99860 363-368 10.1023/A:1005964123955 0166-8595 The minimal photounit of the photosynthetic membranes of the purple non-sulphur bacterium Rhodospirillum rubrum, comprising the reaction centre and the light-harvesting complex has been purified and crystallised in two dimensions in the presence of added phospholipids, and subsequently visualised by electron microscopy after negatively-staining. The position of the reaction centres within the light-harvesting ring has been determined at low resolution by the application of a new analysis for rotationally disordered identical units (here the reaction centres) within a two-dimensional crystalline lattice comprised of perfectly aligned unit cells (here the light-harvesting complexes). The reaction centre was found to preferentially occupy one of four orientations within the light-harvesting complex. The light-harvesting complex appears to be distorted to C4 symmetry, thus assuming a squarish shape when visualised by negative staining. A tentative structural model of the reaction centre-light-harvesting complex photounit which fits the experimental data is proposed. 2D crystals Image processing Membrane protein structure Reaction centre Rhodospirillum rubrum Transmission electron microscopy Dewey 580 Open Access - Licence nationale Springer 45 Département des sciences végétales 163 false Photosynthesis Research 55 2/3 dffca5a0-4acb-4dc0-b679-449f4acf5e84 Article (Published version) Public Stahlberg1998_Article_TheReactionCentreOfThePhotouni.pdf 1351510 application/pdf openAccess Faculté des sciences / Section de biologie / Département des sciences végétales

Title	Published in	Access level	OA Policy	Year	Views	Downloads

The reaction centre of the photounit of Rhodospirillum rubrum is anchored to the light-harvesting complex with four-fold rotational disorder	Photosynthesis Research			1998	371	293

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Dubochet, Jacques