TCDB is operated by the Saier Lab Bioinformatics Group
TCIDNameDomainKingdom/PhylumProtein(s)
*2.A.54.1.1









Mitochondrial serine (and possibly cystine and alanine) carrier, Sideroflexin-1 (SFXN1) of 322 aas and possibly 6 TMSs (Kory et al. 2018). This system is believed to be required for one-carbon metabolism because serine is converted into glycine and formate in the mitochondrion. 

Eukaryota
Metazoa
MTC of Homo sapiens
*2.A.54.1.2









Hypothetical 36.7 KDa protein AH6.2
Eukaryota
Metazoa
AH6.2 of Caenorhabditis elegans
*2.A.54.1.3









Sideroflexin-4 (Breast cancer resistance marker 1)

Eukaryota
Metazoa
Sideroflexin-4 of Homo sapiens
*2.A.54.1.4









Probable mitochondrial transport protein FSF1 (Fungal sideroflexin-1)
Eukaryota
Fungi
FSF1 of Saccharomyces cerevisiae
*2.A.54.1.5









Sideroflexin-5
Eukaryota
Metazoa
Sfxn5 of Mus musculus
*2.A.54.1.6









Sideroflexin-3
Eukaryota
Metazoa
Sfxn3 of Mus musculus
*2.A.54.1.7









Tricarboxylic acid (TCA) transporter of 327 aas and 6 TMSs. Found to be essential for bloodstream-form Trypanosoma brucei through a genome-wide RNAi screen (Schmidt et al. 2018).

Eukaryota
Kinetoplastida
TCA carrier of Trypanosoma brucei
*2.A.54.1.8









Sideroflexin 2, SFXN2 of 322 aas and 5 or 6 TMSs in a 1 or 2 + 2 + 2 TMS arrangement.  SFXN2 is involved in mitochondrial iron metabolism and is localized to the mitochondrial inner membrane (Mon et al. 2019). SFXN2-knockout (KO) cells have an increased mitochondrial iron content and decreases in the heme content and heme-dependent enzyme activities. By contrast, the activities of iron-sulfur cluster-dependent enzymes were unchanged. Abnormal iron metabolism impaired mitochondrial respiration in SFXN2-KO cells and accelerated iron-mediated death (Mon et al. 2019).

Eukaryota
Metazoa
SFXN2 of Homo sapiens
*2.A.54.1.9









Siderofoexin4, SFXN4, of 479 aas and 6 or 7 TMSs.

Eukaryota
Metazoa
SFXN4 of Sturnus vulgaris
*2.A.54.1.10









Sideroflexin-4 isoform X4 of 327 aas and 7 probable TMSs in a 1 + 2 + 2 + 2 TMS arrangement.

Eukaryota
Metazoa
SFXN4 of Pogona vitticeps
*2.A.54.1.11









Uncharacterized protein of 331 aas and 6 putative TMSs in a 2 + 2 + 2 TMS arrangement.

Eukaryota
Oomycetes
UP of Peronospora effusa