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Cytochrome c oxidase subunit I-like superfamily

SCOP classification
Root:   SCOP hierarchy in SUPERFAMILY [ 0] (11)
Class:   Membrane and cell surface proteins and peptides [ 56835] (58)
Fold:   Cytochrome c oxidase subunit I-like [ 81443]
Superfamily:   Cytochrome c oxidase subunit I-like [ 81442]
Families:   Cytochrome c oxidase subunit I-like [ 81441] (4)


Superfamily statistics
Genomes (2,019) Uniprot 2018_03 genome PDB chains (SCOP 1.75)
Domains 4,969 0 8
Proteins 4,959 0 8


Functional annotation
General category Metabolism
Detailed category Energy

Document:
Function annotation of SCOP domain superfamilies

Enzyme Commission (EC)

(show details)
EC termFDR (all)SDEO levelAnnotation (direct or inherited)
Enzyme Commission (EC)Oxidoreductases0Least InformativeDirect
Enzyme Commission (EC)Acting on a heme group of donors0Highly InformativeDirect

Document: EC annotation of SCOP domains

Enzyme Commission (EC)

(show details)
EC termFDR (all)SDEC levelAnnotation (direct or inherited)
Enzyme Commission (EC)Oxidoreductases0Least InformativeDirect
Enzyme Commission (EC)Acting on a heme group of donors0Highly InformativeDirect
Enzyme Commission (EC)Acting on diphenols and related substances as donors0.1956Highly InformativeInherited

Document: EC annotation of SCOP domains

UniProtKB KeyWords (KW)

(show details)
KW termFDR (all)SDKW levelAnnotation (direct or inherited)
Biological processTransport0Least InformativeDirect
Biological processIon transport1Moderately InformativeInherited
Biological processElectron transport0InformativeDirect
Biological processRespiratory chain0Highly InformativeDirect
Biological processIntron homing0Highly InformativeDirect
Biological processHydrogen ion transport0.000000000008746Highly InformativeDirect
Cellular componentMembrane0Least InformativeDirect
Cellular componentMitochondrion0Moderately InformativeDirect
Cellular componentMitochondrion inner membrane0InformativeDirect
DomainTransmembrane0Least InformativeDirect
Molecular functionMetal-binding0Least InformativeDirect
Molecular functionIron0Moderately InformativeDirect
Molecular functionCopper0InformativeDirect
Molecular functionHeme0InformativeDirect
Post-translational modificationOxidoreductase0Moderately InformativeDirect

Document: KW annotation of SCOP domains

InterPro annotation
Cross references IPR000883 SSF81442 Protein matches
Abstract Cytochrome c oxidase is a key enzyme in aerobic metabolism. Proton pumping heme-copper oxidases represent the terminal, energy-transfer enzymes of respiratory chains in prokaryotes and eukaryotes. The CuB-heme a3 (or heme o) binuclear centre, associated with the largest subunit I of cytochrome c and ubiquinol oxidases , is directly involved in the coupling between dioxygen reduction and proton pumping [PubMed8083153, PubMed8049679]. Some terminal oxidases generate a transmembrane proton gradient across the plasma membrane (prokaryotes) or the mitochondrial inner membrane (eukaryotes).

The enzyme complex consists of 3-4 subunits (prokaryotes) up to 13 polypeptides (mammals) of which only the catalytic subunit (equivalent to mammalian subunit I (CO I)) is found in all heme-copper respiratory oxidases. The presence of a bimetallic centre (formed by a high-spin heme and copper B) as well as a low-spin heme, both ligated to six conserved histidine residues near the outer side of four transmembrane spans within CO I is common to all family members [PubMed8013452, PubMed6307356, PubMed2824194]. In contrast to eukaryotes the respiratory chain of prokaryotes is branched to multiple terminal oxidases. The enzyme complexes vary in heme and copper composition, substrate type and substrate affinity. The different respiratory oxidases allow the cells to customize their respiratory systems according to a variety of environmental growth conditions [PubMed8083153].

It has been shown that eubacterial quinol oxidase was derived from cytochrome c oxidase in Gram-positive bacteria and that archaebacterial quinol oxidase has an independent origin. A considerable amount of evidence suggests that proteobacteria (Purple bacteria) acquired quinol oxidase through a lateral gene transfer from Gram-positive bacteria [PubMed8083153].

Nitric oxide reductase (NOR) exists in denitrifying species of archae and eubacteria and is a heterodimer of cytochromes b and c. Phenazine methosulphate can act as acceptor. The prosite signature in this entry recognises the heme-copper site of the nitric oxidases.


InterPro database


PDBeMotif information about ligands, sequence and structure motifs
Cross references PDB entries
Ligand binding statistics
Nucleic-acid binding statistics
Occurrence of secondary structure elements
Occurrence of small 3D structural motifs

PDBeMotif resource

Jump to [ Top of page · SCOP classification · InterPro annotation · PDBeMotif links · Functional annotation · Enzyme Commission (EC) · Enzyme Commission (EC) · UniProtKB KeyWords (KW) ]

Internal database links

Browse genome assignments for this superfamily. The SUPERFAMILY hidden Markov model library has been used to carry out SCOP domain assignments to all genomes at the superfamily level.


Alignments of sequences to 5 models in this superfamily are available by clicking on the 'Alignments' icon above. PDB sequences less than 40% identical are shown by default, but any other sequence(s) may be aligned. Select PDB sequences, genome sequences, or paste in or upload your own sequences.


Browse and view proteins in genomes which have different domain combinations including a Cytochrome c oxidase subunit I-like domain.


Examine the distribution of domain superfamilies, or families, across the major taxonomic kingdoms or genomes within a kingdom. This gives an immediate impression of how superfamilies, or families, are restricted to certain kingdoms of life.


Explore domain occurrence network where nodes represent genomes and edges are domain architectures (shared between genomes) containing the superfamily of interest.

There are 5 hidden Markov models representing the Cytochrome c oxidase subunit I-like superfamily. Information on how the models are built, and plots showing hydrophobicity, match emmission probabilities and insertion/deletion probabilities can be inspected.


Jump to [ Top of page · SCOP classification · InterPro annotation · PDBeMotif links · Functional annotation · Enzyme Commission (EC) · Enzyme Commission (EC) · UniProtKB KeyWords (KW) · Internal database links ]