cd03470

Iron-sulfur protein (ISP) component of the bc(1) complex family, Rieske domain; The Rieske domain is a [2Fe-2S] cluster binding domain involved in electron transfer. The bc(1) complex is a multisubunit enzyme found in many different organisms including uni- and multi-cellular eukaryotes, plants (in their mitochondria) and bacteria. The cytochrome bc(1) and b6f complexes are central components of the respiratory and photosynthetic electron transport chains, respectively, which carry out similar core electron and proton transfer steps. The bc(1) and b6f complexes share a common core structure of three catalytic subunits: cyt b, the Rieske ISP, and either a cyt c1 in the bc(1) complex or cyt f in the b6f complex, which are arranged in an integral membrane-bound dimeric complex. While the core of the b6f complex is similar to that of the bc(1) complex, the domain arrangement outside the core and the complement of prosthetic groups are strikingly different.