首页 | 本学科首页   官方微博 | 高级检索  
   检索      


Structure of the dimeric PufX-containing core complex of Rhodobacter blasticus by in situ atomic force microscopy
Authors:Scheuring Simon  Busselez Johan  Lévy Daniel
Institution:Institut Curie, Unité Mixte de Recherche-CNRS 168 and Laboratoire de Recherche Correspondant-Commissariat à l'Energie Atomique 34V, 11 rue Pierre et Marie Curie, 75231 Paris 05, France. simon.scheuring@curie.fr
Abstract:We have studied photosynthetic membranes of wild type Rhodobacter blasticus, a closely related strain to the well studied Rhodobacter sphaeroides, using atomic force microscopy. High-resolution atomic force microscopy topographs of both cytoplasmic and periplasmic surfaces of LH2 and RC-LH1-PufX (RC, reaction center) complexes were acquired in situ. The LH2 is a nonameric ring inserted into the membrane with the 9-fold axis perpendicular to the plane. The core complex is an S-shaped dimer composed of two RCs, each encircled by 13 LH1 alpha/beta-heterodimers, and two PufXs. The LH1 assembly is an open ellipse with a topography-free gap of approximately 25 A. The two PufXs, one of each core, are located at the dimer center. Based on our data, we propose a model of the core complex, which provides explanation for the PufX-induced dimerization of the Rhodobacter core complex. The QB site is located facing a approximately 25-A wide gap within LH1, explaining the PufX-favored quinone passage in and out of the core complex.
Keywords:
本文献已被 PubMed 等数据库收录!
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号