Holocytochrome-c synthase
In enzymology, a holocytochrome-c synthase (EC 4.4.1.17) is an enzyme that catalyzes the chemical reaction
- holocytochrome c apocytochrome c + heme
| holocytochrome-c synthase | |||||||||
|---|---|---|---|---|---|---|---|---|---|
| Identifiers | |||||||||
| EC number | 4.4.1.17 | ||||||||
| CAS number | 75139-03-6 | ||||||||
| Databases | |||||||||
| IntEnz | IntEnz view | ||||||||
| BRENDA | BRENDA entry | ||||||||
| ExPASy | NiceZyme view | ||||||||
| KEGG | KEGG entry | ||||||||
| MetaCyc | metabolic pathway | ||||||||
| PRIAM | profile | ||||||||
| PDB structures | RCSB PDB PDBe PDBsum | ||||||||
| Gene Ontology | AmiGO / QuickGO | ||||||||
| |||||||||
| Cytochrome c/c1 heme lyase | |||||||||
|---|---|---|---|---|---|---|---|---|---|
| Identifiers | |||||||||
| Symbol | Cyto_heme_lyase | ||||||||
| Pfam | PF01265 | ||||||||
| InterPro | IPR000511 | ||||||||
| PROSITE | PDOC00647 | ||||||||
| |||||||||
Hence, this enzyme has one substrate, holocytochrome c, and two products, apocytochrome c and heme.
This enzyme belongs to the family of lyases, specifically the class of carbon-sulfur lyases. The systematic name of this enzyme class is holocytochrome-c apocytochrome-c-lyase (heme-forming). Other names in common use include cytochrome c heme-lyase, holocytochrome c synthetase, and holocytochrome-c apocytochrome-c-lyase. This enzyme participates in porphyrin and chlorophyll metabolism.
Cytochrome c haem-lyase (CCHL) and cytochrome Cc1 haem-lyase (CC1HL) 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. Both patterns contain conserved histidine, tryptophan and acidic residues which could be important for the interaction of the enzymes with the apoproteins and/or the haem group.[1]
The human enzyme, HCCS, processes both cytochromes c and c1.[2]
References
- Zollner A, Rodel G, Haid A (August 1992). "Molecular cloning and characterization of the Saccharomyces cerevisiae CYT2 gene encoding cytochrome-c1-heme lyase". Eur. J. Biochem. 207 (3): 1093–100. doi:10.1111/j.1432-1033.1992.tb17146.x. PMID 1499554.
- Bernard DG, Gabilly ST, Dujardin G, Merchant S, Hamel PP (December 2003). "Overlapping specificities of the mitochondrial cytochrome c and c1 heme lyases". The Journal of Biological Chemistry. 278 (50): 49732–42. doi:10.1074/jbc.M308881200. PMID 14514677.
- Dumont ME, Ernst JF, Hampsey DM, Sherman F (1987). "Identification and sequence of the gene encoding cytochrome c heme lyase in the yeast Saccharomyces cerevisiae". EMBO J. 6 (1): 235–41. doi:10.1002/j.1460-2075.1987.tb04744.x. PMC 553382. PMID 3034577.