InterPro domain: IPR000511

Holocytochrome c-type synthase (HCCS, also known as cytochrome c-type heme lyase) ( 4.4.1.17 ) and holocytochrome-c1 synthase (CC1HL, also known as cytochrome c1 heme lyase) [ 1 ] are mitochondrial enzymes that catalyse the covalent attachment of a haem group on two cysteine residues of cytochrome c and c1. These two enzymes are functionally and evolutionary related. There are two conserved regions, the first is located in the central section and the second in the C-terminal section. These enzymes contain a conserved histidine, which is key to interact with the heme iron and to form the HCCS:heme complex, the platform for interaction with apocytochrome c [ 2 ].

1. Molecular cloning and characterization of the Saccharomyces cerevisiae CYT2 gene encoding cytochrome-c1-heme lyase. Eur. J. Biochem. 207, 1093-100
2. Human mitochondrial holocytochrome c synthase's heme binding, maturation determinants, and complex formation with cytochrome c. Proc Natl Acad Sci U S A 110, E788-97