bc1 complex and its relationship to the b6f complex

Introduction

   The cytochrome b₆f complex is the intermediate protein complex in linear photosynthetic elecron transport.  It is found in the thylakoid membrane of higher plants and cyanobacteria. The core complex is comprised of four proteins: cytochrome b₆, subunit IV, cytochrome f, and the Rieske center, an iron-sulfur protein.  Electrons are transferred through the b₆f complex through a plastoquinol, leading to the formation of a plastoquinone and 2H⁺ in the thylakoid lumen.  The terminal electron acceptor in the b6f complex is cytochrome f, which is oxidized by plastocyanin.

Q-cycle

bc₁ and b₆f sites of interest