Protein Domain : Di-haem cytochrome, transmembrane IPR016174

Type	Homologous_superfamily
Description	This entry represents a haem-binding domain with a 4-helical bundle structure that is found in transmembrane di-haem cytochromes. The domain contains four transmembrane helices in an up-and-down bundle, and binds two haem groups in between the helices; three of the four haem-binding residues is conserved between family members. Proteins containing this domain include:N-terminal domain of mitochondrial cytochrome b subunit, in which the domain contains an extra transmembrane linker helix that is absent in plant and cyanobacteria subunits [ ].Cytochrome b6 subunit of the cytochrome b6f complex, which provides the electronic connection between the photosystems I and II reaction centres of oxygenic photosynthesis, and generates a transmembrane electrochemical proton gradient for adenosine triphosphate synthesis [ ].Cytochrome gamma subunit of formate dehydrogenase-N (Fdn-N), which acts as a major component of Escherichia coli nitrate respiration [ ].Please note, this entry also identifies a number of proteins that are cleaved into two chains - a truncated non-functional cytochrome oxidase 1 and an intron-encoded endonuclease.
Short Name	Di-haem_cyt_TM