Projection map of cytochrome b6 f complex at 8 A resolution.
The structure of the cytochrome b6 f complex has been investigated by electron microscopy and image analysis of thin three-dimensional crystals. Electron micrographs of negatively stained specimens were recorded and showed optical diffraction peaks to 10 A resolution. A projection map was calculated at 8 A resolution and showed the presence of cytochrome b6 f dimers. The extramembrane part of each monomer featured a C shape, with mean external diameter approximately of 53 A and an internal groove approximately 14 A long and approximately 9 A wide. Within each monomer, strong features were clearly resolved and tentatively attributed to some of the subunits of the cytochrome b6 f complex. The data are consistent with the Rieske iron-sulfur protein lying close to the monomer-monomer interface and the heme-bearing domain of cytochrome f far from it.
Mosser
G
G
Institut Curie, Section de Recherche UMR-CNRS 168 and LRC-CEA 8, 11 rue Pierre et Marie Curie, F-75231 Paris Cedex, France.
Breyton
C
C
Olofsson
A
A
Popot
J L
JL
Rigaud
J L
JL
D000818:Animals; D016825:Chlamydomonas reinhardtii; D003573:Cytochrome b Group / Q000648:ultrastructure*; D045346:Cytochrome b6f Complex; D019281:Dimerization; D007091:Image Processing, Computer-Assisted; D008854:Microscopy, Electron; D011487:Protein Conformation; D017550:Spectroscopy, Fourier Transform Infrared; D014961:X-Ray Diffraction
D003573:Cytochrome b Group; D045346:Cytochrome b6f Complex