X-Ray Structure of Rhodobacter Capsulatus Cytochrome bc (1): Comparison with its Mitochondrial and Chloroplast Counterparts.

Ubihydroquinone: cytochrome (cyt)c oxidoreductase, or cyt bc (1), is a widespread, membrane integral enzyme that plays a crucial role during photosynthesis and respiration. It is one of the major contributors of the electrochemical proton gradient, which is subsequently used for ATP synthesis. The simplest form of the cyt bc (1) is found in bacteria, and it contains only the three ubiquitously conserved catalytic subunits: the Fe-S protein, cyt b and cyt c (1).