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372  structures 1533  species 0  interactions 16008  sequences 228  architectures

Clan: CHCH (CL0351)


Coiled-coil helix coiled-coil helix superfamily Add an annotation

The conserved [coiled coil 1]-[helix 1]-[coiled coil 2]-[helix 2] domain (CHCH domain) superfamily members include NADH-ubiquinone oxidoreductases, some cytochrome oxidases and yeast mitochondrial ribosomal proteins. Within each helix of the CHCH domain there are two cysteines present in a C-X9-C motif.

This clan contains 8 families and the total number of domains in the clan is 16008. The clan was built by A Bateman.


This clan contains the following 8 member families:


Domain organisation

Below is a listing of the unique domain organisations or architectures from this clan. More...

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The table below shows the number of occurrences of each domain throughout the sequence database. More...

Pfam family Num. domains Alignment
CHCH (PF06747) 4168 (26.0%) View
COX6B (PF02297) 3590 (22.4%) View
Cmc1 (PF08583) 2970 (18.6%) View
COX17 (PF05051) 1429 (8.9%) View
NDUF_B7 (PF05676) 1428 (8.9%) View
MTCP1 (PF08991) 868 (5.4%) View
Ndufs5 (PF10200) 844 (5.3%) View
CX9C (PF16860) 711 (4.4%) View
Total: 8 Total: 16008 Clan alignment

Please note: Clan alignments can be very large and can cause problems for some browsers. Read the note above before viewing.

Family relationships

This diagram shows the relationships between members of this clan. More...

Species distribution

Tree controls


This tree shows the occurrence of the domains in this clan across different species. More...



For those sequences which have a structure in the Protein DataBank, we use the mapping between UniProt, PDB and Pfam coordinate systems from the MSD group, to allow us to map Pfam domains onto UniProt three-dimensional structures. The table below shows the mapping between the Pfam families in this clan, the corresponding UniProt entries, and the region of the three-dimensional structures that are available for that sequence.

Loading structure mapping...