Protein Domain : Cytochrome c, class IC IPR008168

Type	Family
Description	Cytochrome c (CytC) proteins can be defined as electron-transfer proteins having one or several haem c groups, bound to the protein by one or, more generally, two thioether bonds involving sulphydryl groups of cysteine residues. The fifth haem iron ligand is always provided by a histidine residue. CytC possess a wide range of properties and function in a large number of different redox processes.Ambler [ ] recognised four classes of cytC.Class I includes the low-spin soluble CytC of mitochondria and bacteria, with the haem-attachment site towards the N terminus, and the sixth ligand provided by a methionine residue about 40 residues further on towards the C terminus. On the basis of sequence similarity, class I CytC were further subdivided into five classes, IA to IE. Class IC, 'split-alpha-band' Cyt C, possess a widened or split alpha-band of lowered absorptivity. This class includes dihaem Cyt C4 and monohaem Cyt C6 (Cyt C-553) and Cyt C-554.The 3D structures of Chlamydomonas reinhardtii Cyt C6 [ ] and Desulfovibrio vulgaris Cyt C-553 [] have been determined. The proteins consist of 4 α-helices; three 'core' helices form a 'basket' around the haem group, with one haem edge exposed to the solvent.
Short Name	Cyt_C_IC