TCDB is operated by the Saier Lab Bioinformatics Group
TCIDNameDomainKingdom/PhylumProtein(s)
9.B.14.1.1









The cytochrome c biogenesis protein, CcmF
Bacteria
Pseudomonadota
CcmF (Ccl1) of Rhodobacter capsulatus
9.B.14.1.2









The cytochrome c biogenesis protein, CycK
Bacteria
Pseudomonadota
CycK of Bradyrhizobium japonicum
9.B.14.1.3









The cytochrome c biogenesis protein, CcmF
Bacteria
Pseudomonadota
CcmF (CycK) of E. coli (P33927)
9.B.14.1.4









C-type biosynthesis protein, CcmF (620 aas; 17 TMSs) (resembles 9.B.67.3.3, and possibly APC family (2.A.3) members)

Eukaryota
Rhodophyta
CcmF of Cyanidioschyzon merolae (Q9ZZP7)
9.B.14.1.5









Cytochrome C-type biogenesis protein, CcmF 

Archaea
Euryarchaeota
CcmF of Haloarcula marismortui (Q5V2F3)
9.B.14.1.6









Mitochondrial cytochrome C-type biogenesis protein, CcmF of 442 aas and 6 - 8 TMSs.

Eukaryota
Viridiplantae, Streptophyta
CcmF of Arabidopsis thaliana (P93286)
9.B.14.1.7









Cytochrome biogenesis protein, CcmF (involved also in pyoverdine maturation) (Baert et al. 2008). It is 657 aas long with 15 TMSs in a 14 + 1 TMS arrangement.

Bacteria
Pseudomonadota
CcmF of Pseudomonas aeruginosa
9.B.14.1.8









MURF1 protein of 443 aas and 16 TMSs

Eukaryota
Euglenozoa
MURF1 of Leishmania tarentolae (Sauroleishmania tarentolae)
9.B.14.1.9









Putative XkR8 (TC family 2.A.112) homologue of 235 aas and 6 TMSs.

Bacteria
Campylobacterota
XkR8 homologue of Campylobacter jejuni
9.B.14.1.10









Uncharacterized protein of 796 aas and 19 TMSs

Bacteria
Spirochaetota
UP of Leptospira interrogans
9.B.14.1.11









Heme maturase of 518 aas and 13 TMSs, YejR

Eukaryota
Ciliophora
YejR of Tetrahymena thermophila
9.B.14.1.12









Uncharacterized protein of 285 aas and 6 TMSs

Eukaryota
Fungi, Ascomycota
UP of Candida albicans
9.B.14.1.13









AgrC of 429 aas and 6 TMSs

Bacteria
Bacillota
AgrC of Stahpylococcus epidermidis
9.B.14.1.14









Uncharacterized protein of 225 aas and 6 TMSs.

Bacteria
Thermotogota
UP of Petrotoga mobilis
9.B.14.1.15









Uncharacterized protein of 263 aas and 7 TMSs

Bacteria
Fusobacteriota
UP of Fusobacterium nucleatum
9.B.14.1.16









Uncharacterized protein of 257 aas and 6 TMSs

Bacteria
Bacillota
UP of Caldicellulosiruptor lactoaceticus
9.B.14.1.17









Uncharacterized protein of 434 aas and 7 TMSs.

Bacteria
Bacillota
UP of Roseburia intestinalis
9.B.14.1.18









Uncharacterized GHKL domain-containing protein of 445 aas and 6 TMSs.

Bacteria
Bacillota
UP of Clostridium hungatei
9.B.14.1.20









Uncharacteerized ATP-binding protein of 424 aas and 7 N-terminal TMSs and a C-terminal hydrophilic domain.

Bacteria
Bacillota
UP of Ruminococcus flavefaciens
9.B.14.1.21









CcmA/CcmD proteins, probably involved in cytochorme c matureation (heme insertion). CcmA iis of 353 aas with 9 TMSs, while CcmD is of 240 aas with 6 TMSs.  They may function with CcmB (see TC# 3.A.1.107.5 (Gupta et al. 2022).

Archaea
Euryarchaeota
CcmA/CcmD of Methanosarcina acetivorans
9.B.14.2.1









The putative heme exporter, HelC
Bacteria
Pseudomonadota
HelC of Rhodobacter capsulatus (P29961)
9.B.14.2.2









The putative heme exporter, CcmC (CycZ). This protein is also listed under TC# 3.A.1.107.1 as part of an ABC transporter
Bacteria
Pseudomonadota
CcmC (CycZ) of Bradirhizobium japonicum (P30962)
9.B.14.2.3









The putative heme exporter, CycZ (CcmC)
Bacteria
Pseudomonadota
CycZ (CcmC) of E. coli (P0ABM1)
9.B.14.2.4









Putative heme exporter, CcmC; also involved in pyoverdine maturation (Baert et al. 2008).

Bacteria
Pseudomonadota
CcmC of Pseudomonas aeruginosa
9.B.14.2.5









ABC-type cytochrome c biogenesis putative heme transport system permease component C of 234 aas
Bacteria
Ignavibacteriota
Putative ABC-type cytochrome c biogenesis transport system permease component of Melioribacter roseus
9.B.14.3.1









Cytochrome c biogenesis protein, CcsBA (936 aas; 10 TMSs; 14 TMSs predicted by the WHAT program (Frawley and Kranz, 2009).  May be a bifunctional protein with heme transport (export from the cytoplasm to the periplasm) and attachment to apocytochrome c (cytochrome c synthetase) activities.  Two heme binding sites have been identified in a homologue, one in the membrane and one on the external surface (on the periplasmic side of the membrane) (Sutherland et al. 2018). Mendez et al. 2022 described cryo-EM structures of CcsBA, which, as noted above, is a bifunctional heme transporter and cytochrome c (cyt c) synthase. Models built from the cryo-EM densities show that CcsBA is trapped with heme in two conformations, closed and open states. The closed state has heme located solely at a transmembrane (TM) site, with a large periplasmic domain oriented such that access of heme to the cytochrome acceptor is prevented. The open conformation contains two heme moieties, one in the TM-heme site and another in an external site (P-heme site). The presence of heme in the periplasmic site at the base of a chamber induces a large conformational shift that exposes the heme for reaction with apocytochrome c (apocyt c). Consistent with these structures, in vivo and in vitro cyt c synthase studies suggest a mechanism for transfer of the periplasmic heme to cytochrome (Mendez et al. 2022).

Bacteria
Campylobacterota
CcsBA of Helicobacter hepaticus (Q7VHG9)
9.B.14.3.2









Cytochrome c biogenesis protein CcsA
Bacteria
Cyanobacteriota
ccsA of Prochlorococcus marinus
9.B.14.3.3









Cytochrome c biogenesis protein CcsA or Ccs1 of 353 aas.  Required during biogenesis of c-type cytochromes (cytochrome c6 and cytochrome f) at the step of heme attachment (Inoue et al. 1997).

Eukaryota
Viridiplantae, Chlorophyta
CcsA of Chlamydomonas reinhardtii
9.B.14.3.4









Cytochrome c biogenesis protein of 327 aas and 6 established TMSs, CcsA.

Bacteria
Actinomycetota
CcsA of Mycobacterium leprae
9.B.14.3.5









Membrane protein of 266 aas and 8 putative TMSs.

Bacteria
Pseudomonadota
Membrane protein of Pseudomonas aeruginosa
9.B.14.3.6









Putative cytochrome c assembly protein, YpjD of 263 aas and 8 TMSs.  In an operon with YfjD, a putative Mg2+uptake protein (TC# 9.B.20.1.4).

Bacteria
Pseudomonadota
YpjD of E. coli
9.B.14.3.7









Cytochrome c biogenesis protein, CcsA, of 309 aas and 8 TMSs.  May be a bifunctional protein with heme transport (export from the cytoplasm to the periplasm) and attachment to apocytochrome c (cytochrome c synthetase) activities.  Two heme binding sites have been identified in a homologue, one in the membrane and one on the external surface (on the periplasmic side of the membrane) (Sutherland et al. 2018).

Bacteria
Cyanobacteriota
CcsA of Prochlorococcus marinus
9.B.14.3.8









Cytochrome c biogenesis protein, CcsA, of 309 aas and 8 TMSs.  May be a bifunctional protein with heme transport (export from the cytoplasm to the periplasm) and attachment to apocytochrome c (cytochrome c synthetase) activities.  Two heme binding sites have been identified in a homologue, one in the membrane and one on the external surface (on the periplasmic side of the membrane) (Sutherland et al. 2018).

Bacteria
Campylobacterota
CcsB of Helicobacter pylori
9.B.14.3.9









Cytochrome c biogenesis protein, CcsB, of 1041 aas and 14 TMSs.  May be a bifunctional protein with heme transport (export from the cytoplasm to the periplasm) and attachment to apocytochrome c (cytochrome c synthetase) activities.  Two heme binding sites have been identified in a homologue, one in the membrane and one on the external surface (on the periplasmic side of the membrane) (Sutherland et al. 2018).

Bacteria
Bacteroidota
CcsB of Flavobacterium psychrophilum
9.B.14.3.10









Uncharacterized protein of 271 aas and 8 TMSs.

Bacteria
Planctomycetota
UP of Gemmataceae bacterium (freshwater metagenome)
9.B.14.4.1









XkR8 homologue of 383 aas and 11 TMSs.

Bacteria
Spirochaetota
XkR8 homologue of Brachyspira murdochii
9.B.14.4.2









Putative XkR8 homologue of 404 aas and 11 TMSs.

Bacteria
Spirochaetota
XkR8 homologue of Brachyspira pilosicoli
9.B.14.4.3









Putative XkR8 homologue of 587 aas and 12 TMSs.

Bacteria
Mycoplasmatota
Putative XkR8 homologue of Mycoplasma mycoides
9.B.14.4.4









Uncharacterized protein of 431 aas and 5 TMSs in a 1 (N-terminal) + 4 (C-terminal) TMS arrangement.

Eukaryota
Apicomplexa
UP of Plasmodium yoelii
9.B.14.4.5









O-antigen polymerase of 439 aas and 10 TMSs.

Bacteria
Pseudomonadota
Polymerase of Candidatus Pelagibacter
9.B.14.4.6









Uncharacterized protein of 497 aas and 12 TMSs.

Bacteria
Mycoplasmatota
UP of Mycoplasma collis
9.B.14.5.1









Putative bacteriocin immunity protein of 572 aas and 14 putative TMSs.

Bacteria
Bacillota
Imm protein of Bacillus cereus
9.B.14.5.2









Uncharacterized protein of 588 aas and about 15 TMSs.

Bacteria
Bacillota
UP of Bacillus cereus