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253  structures 7633  species 0  interactions 74433  sequences 919  architectures

Clan: 2heme_cytochrom (CL0328)


Transmembrane di-heme cytochrome superfamily Add an annotation

This superfamily includes a variety of different heme binding cytochromes.

This clan contains 11 families and the total number of domains in the clan is 74433. The clan was built by A Bateman.


This clan contains the following 11 member families:

COX15-CtaA Cytochrom_B561 Cytochrom_B_N_2 Cytochrom_C_asm Cytochrome_B DUF2231 DUF2427 DUF4405 DUF6529 Ferric_reduct Ni_hydr_CYTB

External database links

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
Ferric_reduct (PF01794) 20466 (27.5%) View
Cytochrom_C_asm (PF01578) 13522 (18.2%) View
Ni_hydr_CYTB (PF01292) 11218 (15.1%) View
Cytochrom_B561 (PF03188) 8343 (11.2%) View
COX15-CtaA (PF02628) 8141 (10.9%) View
Cytochrome_B (PF00033) 4593 (6.2%) View
DUF2231 (PF09990) 3385 (4.5%) View
Cytochrom_B_N_2 (PF13631) 2250 (3.0%) View
DUF2427 (PF10348) 1532 (2.1%) View
DUF4405 (PF14358) 738 (1.0%) View
DUF6529 (PF20139) 245 (0.3%) View
Total: 11 Total: 74433 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.

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