Cytochrome c family

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Cytochrome c
Identifiers
Symbol	Cytochrom_C
Pfam	PF00034
InterPro	IPR003088
PROSITE	PDOC00169
SCOP	1cry
OPM family	78
OPM protein	1hrc
Available PDB structures: 1ql3D:80-176 1ql4D:80-176 1i6eA:80-176 1c7mA:80-176 1i6dA:80-176 1ccr :12-111 2b4zA:4-103 2pcbB:4-103 1giw :4-103 1m60A:4-103 1fi7A:4-103 1ocd :4-103 1lc1A:4-103 1lc2A:4-103 1crcB:4-103 1fi9A:4-103 1hrc :4-103 1i5tA:4-103 1u75B:4-103 1akk :4-103 1wejF:4-103 2frc :4-103 2giw :4-103 1j3sA:4-103 1i55A:3-102 1lfmA:3-102 1i54B:3-102 3cytO:3-102 5cytR:3-102 1cycA:4-103 1ytc :13-112 1yeb :13-107 1yea :13-112 2pccB:9-108 2b11D:9-108 1u74D:9-108 1crj :9-108 2ycc :9-108 1s6vB:9-108 2b10D:9-108 1csu :9-108 1crg :9-108 1ctz :9-108 1raq :9-108 1irv :9-108 1yfc :9-108 1nmiA:9-108 1kyoW:9-108 1crh :9-108 1rap :9-108 1csv :9-108 2b0zB:9-108 1csx :9-108 1cif :9-108 1yic :9-108 1chj :9-108 1ycc :9-108 2b12B:9-108 1lmsA:9-108 1cig :9-108 1cie :9-108 1cri :9-108 1chh :9-108 1csw :9-108 1cih :9-108 1irw :9-108 1chi :9-108 1fhb :9-108 1cty :9-108 1h29D:103-130 1gwsA:103-130 1io3A:23-121 1cry :23-121 1co6A:23-121 1jdlA:5-119 1i8oA:28-139 1i8pA:28-139 1fj0C:28-139 1hh7A:28-139 1qn2B:4-100 1hroA:8-106 1c2rA:24-136 1c2n :24-136 2bh5X:25-139 2bgvX:25-139 2bh4X:25-139 1cot :25-139 155c :25-137 1w2lA:223-316 2c8sA:79-157 2mtaC:68-146 1e2rA:83-160 1h9yB:83-160 1aofB:83-160 1hcmB:83-160 1qksB:83-160 1gq1B:83-160 1hj3A:83-160 1dy7B:83-160 1aoqA:83-160 1hj4B:83-160 1hj5B:83-160 1aomB:83-160 1h9xB:83-160 1nnoB:61-138 1gjqB:61-138 1n90A:61-138 1bl9A:61-138 1n50A:61-138 1n15A:61-138 1hzvA:61-138 1nirB:61-138 1hzuA:61-138 1dt1A:20-108 1focA:1-91 1qyzA:1-91 1c52C:1-91 1r0qA:1-91 1m6zA:24-109 1m70A:24-109 1etpB:24-109 1cnoE:4-83 1dvh :25-103 1dwlB:25-103 2dvh :25-103 1fcdD:26-102 1kx2A:22-99 1kx7A:22-99 1t59A:31-109 1c6s :3-81 1gdvA:28-106 1t58A:27-112 1kibF:3-85 1f1fA:3-85 1c6oA:4-84 1c6rA:4-84 1ctj :4-84 1jx8B:4-84 1ced :4-84 1a2s :4-84 1cyi :61-141 1cyj :61-141 1ls9A:6-86 1e29A:51-148 1f1cB:24-121 1igkJ:24-121 1fi3A:23-104 1cor :23-104 1cch :23-104 2pac :23-104 1dvvA:23-104 351c :23-104 451c :23-104 1a56N:23-103 1a8cN:23-103 1ynrA:19-98 1ayg :19-98 1c75A:22-92 1b7vA:22-92 1n9cA:22-92 1k3hA:22-92 1k3gA:22-92

Cytochromes c (cytC) are electron-transfer proteins having one or several heme 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. Cytochromes c possess a wide range of properties and function in a large number of different redox processes^[1]. The founding member of this family is mitochondrial cytochrome c.

Ambler^[2] recognized 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 IB includes the eukaryotic mitochondrial cytC and prokaryotic 'short' cyt c2 exemplified by Rhodopila globiformis cyt c2; class IA includes 'long' cyt c2, such as Rhodospirillum rubrum cyt c2 and Aquaspirillum itersonii cytc-550, which have several extra loops by comparison with class IB cytC.

[edit] Subfamilies

Bacterial cytochrome c, class IC IPR008169

[edit] Human proteins containing this domain

CYCS;

[edit] References

^ Moore GR, Pettigrew GW (1987). "": -.
^ Ambler RP (1991). "Sequence variability in bacterial cytochromes c". Biochim. Biophys. Acta 1058 (1): 42-47. PMID 1646017.