Please note: this site relies heavily on the use of javascript. Without a javascript-enabled browser, this site will not function correctly. Please enable javascript and reload the page, or switch to a different browser.
161  structures 6822  species 16  interactions 28539  sequences 209  architectures

Family: Cytochrome_CBB3 (PF13442)

Summary: Cytochrome C oxidase, cbb3-type, subunit III

Pfam includes annotations and additional family information from a range of different sources. These sources can be accessed via the tabs below.

The Pfam group coordinates the annotation of Pfam families in Wikipedia, but we have not yet assigned a Wikipedia article to this family. If you think that a particular Wikipedia article provides good annotation, please let us know.

This tab holds the annotation information that is stored in the Pfam database. As we move to using Wikipedia as our main source of annotation, the contents of this tab will be gradually replaced by the Wikipedia tab.

Cytochrome C oxidase, cbb3-type, subunit III Provide feedback

No Pfam abstract.

Internal database links

External database links

This tab holds annotation information from the InterPro database.

InterPro entry IPR009056

After cytochrome c is synthesized in the cytoplasm as apocytochrome c, it is transported through the outer mitochondrial membrane to the intermembrane space, where haem is covalently attached by thioester bonds to two cysteine residues located in the cytochrome c centre. Cytochrome c is required during oxidative phosphorylation as an electron shuttle between Complex III (cytochrome c reductase) and IV (cytochrome c oxidase). In addition, cytochrome c is involved in apoptosis in more complex organisms such as Xenopus, rats and humans. Cellular stress can induce cytochrome c release from the mitochondrial membrane. In mammals, cytochrome c triggers the assembly of the apoptosome, consisting of cytochrome c, Apaf-1 and dATP, which activates caspase-9, leading to cell death [PUBMED:12729583, PUBMED:10707095]. There are several different members of the cytochrome c family with different functional roles, for instance cytochrome c549 is associated with photosystem II [PUBMED:11315568].

The known structures of c-type cytochromes have six different classes of fold. Of these, four are unique to c-type cytochromes [PUBMED:12594933, PUBMED:2166169]. The consensus sequence for the cytochrome c centre is Cys-X-X-Cys-His, where the histidine residue is one of the two axial ligands of the haem iron [PUBMED:10647174]. This arrangement is shared by all proteins known to belong to the cytochrome c family, which presently includes both mono-haem proteins and multi-haem proteins. This entry represents mono-haem cytochrome c proteins (excluding class II and f-type cytochromes), such as cytochromes c, c1, c2, c5, c555, c550 to c553, c556, and c6.

Cytochrome c-type centres are also found in the active sites of many enzymes, including cytochrome cd1-nitrite reductase as the N-terminal haem c domain, in quinoprotein alcohol dehydrogenase as the C-terminal domain, in Quinohemoprotein amine dehydrogenase A chain as domains 1 and 2, and in the cytochrome bc1 complex as the cytochrome bc1 domain.

Gene Ontology

The mapping between Pfam and Gene Ontology is provided by InterPro. If you use this data please cite InterPro.

Domain organisation

Below is a listing of the unique domain organisations or architectures in which this domain is found. More...

Loading domain graphics...

Pfam Clan

This family is a member of clan Cytochrome-c (CL0318), which has the following description:

This family includes proteins where a covalently-bound haem completes the core. The core is three helices in an open folded leaf formation. The members are monodomain cytochromes.

The clan contains the following 13 members:

CCP_MauG Cytochrom_C Cytochrom_C1 Cytochrom_C550 Cytochrome-c551 Cytochrome_CBB3 Dehyd-heme_bind DHC DHOR DUF1924 FixO Haem_bd PSCyt1

Alignments

We store a range of different sequence alignments for families. As well as the seed alignment from which the family is built, we provide the full alignment, generated by searching the sequence database using the family HMM. We also generate alignments using four representative proteomes (RP) sets, the NCBI sequence database, and our metagenomics sequence database. More...

View options

We make a range of alignments for each Pfam-A family. You can see a description of each above. You can view these alignments in various ways but please note that some types of alignment are never generated while others may not be available for all families, most commonly because the alignments are too large to handle.

  Seed
(171)
Full
(28539)
Representative proteomes NCBI
(34766)
Meta
(4828)
RP15
(887)
RP35
(2452)
RP55
(3721)
RP75
(5034)
Jalview View  View  View  View  View  View  View  View 
HTML View    View  View  View       
PP/heatmap 1   View  View  View       
Pfam viewer View  View             

1Cannot generate PP/Heatmap alignments for seeds; no PP data available

Key: ✓ available, x not generated, not available.

Format an alignment

  Seed
(171)
Full
(28539)
Representative proteomes NCBI
(34766)
Meta
(4828)
RP15
(887)
RP35
(2452)
RP55
(3721)
RP75
(5034)
Alignment:
Format:
Order:
Sequence:
Gaps:
Download/view:

Download options

We make all of our alignments available in Stockholm format. You can download them here as raw, plain text files or as gzip-compressed files.

  Seed
(171)
Full
(28539)
Representative proteomes NCBI
(34766)
Meta
(4828)
RP15
(887)
RP35
(2452)
RP55
(3721)
RP75
(5034)
Raw Stockholm Download   Download   Download   Download   Download   Download   Download   Download  
Gzipped Download   Download   Download   Download   Download   Download   Download   Download  

You can also download a FASTA format file containing the full-length sequences for all sequences in the full alignment.

External links

MyHits provides a collection of tools to handle multiple sequence alignments. For example, one can refine a seed alignment (sequence addition or removal, re-alignment or manual edition) and then search databases for remote homologs using HMMER3.

HMM logo

HMM logos is one way of visualising profile HMMs. Logos provide a quick overview of the properties of an HMM in a graphical form. You can see a more detailed description of HMM logos and find out how you can interpret them here. More...

Trees

This page displays the phylogenetic tree for this family's seed alignment. We use FastTree to calculate neighbour join trees with a local bootstrap based on 100 resamples (shown next to the tree nodes). FastTree calculates approximately-maximum-likelihood phylogenetic trees from our seed alignment.

Note: You can also download the data file for the tree.

Curation and family details

This section shows the detailed information about the Pfam family. You can see the definitions of many of the terms in this section in the glossary and a fuller explanation of the scoring system that we use in the scores section of the help pages.

Curation View help on the curation process

Seed source: Jackhmmer:Q2Y8Z1
Previous IDs: none
Type: Domain
Author: Coggill P
Number in seed: 171
Number in full: 28539
Average length of the domain: 79.60 aa
Average identity of full alignment: 24 %
Average coverage of the sequence by the domain: 32.39 %

HMM information View help on HMM parameters

HMM build commands:
build method: hmmbuild -o /dev/null HMM SEED
search method: hmmsearch -Z 80369284 -E 1000 --cpu 4 HMM pfamseq
Model details:
Parameter Sequence Domain
Gathering cut-off 27.0 22.0
Trusted cut-off 27.0 22.0
Noise cut-off 26.9 21.9
Model length: 67
Family (HMM) version: 2
Download: download the raw HMM for this family

Species distribution

Sunburst controls

Show

Weight segments by...


Change the size of the sunburst

Small
Large

Colour assignments

Archea Archea Eukaryota Eukaryota
Bacteria Bacteria Other sequences Other sequences
Viruses Viruses Unclassified Unclassified
Viroids Viroids Unclassified sequence Unclassified sequence

Selections

Align selected sequences to HMM

Generate a FASTA-format file

Clear selection

This visualisation provides a simple graphical representation of the distribution of this family across species. You can find the original interactive tree in the adjacent tab. More...

Loading sunburst data...

Tree controls

Hide

The tree shows the occurrence of this domain across different species. More...

Loading...

Please note: for large trees this can take some time. While the tree is loading, you can safely switch away from this tab but if you browse away from the family page entirely, the tree will not be loaded.

Interactions

There are 16 interactions for this family. More...

Cu-oxidase Copper-bind COX3 FixO COX1 Cytochrome_CBB3 PQQ Mo-co_dimer Oxidored_molyb COX2 PQQ_2 COX1 Cu-oxidase_3 FAD_binding_4 Cytochrom_D1 FAD-oxidase_C

Structures

For those sequences which have a structure in the Protein DataBank, we use the mapping between UniProt, PDB and Pfam coordinate systems from the PDBe group, to allow us to map Pfam domains onto UniProt sequences and three-dimensional protein structures. The table below shows the structures on which the Cytochrome_CBB3 domain has been found. There are 161 instances of this domain found in the PDB. Note that there may be multiple copies of the domain in a single PDB structure, since many structures contain multiple copies of the same protein seqence.

Loading structure mapping...