9.B.169 The Integral Membrane Protein (8 -10 TMSs) YeiB or DUF418 (YeiB) Family

The E. coli YeiB and B. subtilis YxaH proteins contain Pfam domains YeiB (the whole protein) and DUF418 (the C-terminal 4-5 TMS domain). This TC family includes proteins annotated as having DUF1624 and DUF5009 domains as well as DUF418. This family may be distantly related to TC family 9.B.97.

This family belongs to the Transmembrane Acyl Transferease (TmAT) Superfamily.



Durand, S., M. Feldhammer, E. Bonneil, P. Thibault, and A.V. Pshezhetsky. (2010). Analysis of the biogenesis of heparan sulfate acetyl-CoA:α-glucosaminide N-acetyltransferase provides insights into the mechanism underlying its complete deficiency in mucopolysaccharidosis IIIC. J. Biol. Chem. 285: 31233-31242.

El Yacoubi, B., S. Bonnett, J.N. Anderson, M.A. Swairjo, D. Iwata-Reuyl, and V. de Crécy-Lagard. (2006). Discovery of a new prokaryotic type I GTP cyclohydrolase family. J. Biol. Chem. 281: 37586-37593.

Fan, X., H. Zhang, S. Zhang, R.D. Bagshaw, M.B. Tropak, J.W. Callahan, and D.J. Mahuran. (2006). Identification of the gene encoding the enzyme deficient in mucopolysaccharidosis IIIC (Sanfilippo disease type C). Am J Hum Genet 79: 738-744.

Hirooka, K. and Y. Fujita. (2011). Identification of aromatic residues critical to the DNA binding and ligand response of the Bacillus subtilis QdoR (YxaF) repressor antagonized by flavonoids. Biosci. Biotechnol. Biochem. 75: 1325-1334.


TC#NameOrganismal TypeExample

9 or 10 TMS protein of 402 aas of unknown function with a C-terminal DUF418 domain and a full length YeiB domain, YxaH. The expression of its gene is regulated by two repressors, LmrA and QdoR, which also regulate the lmrAB operon which encodes LmrA as well as the multidrug resistance MFS drug exporter, LmrB (TC# 2.A.1.3.61) (Hirooka and Fujita 2011). Therefore, YxaH could be an MDR pump. Both of the two repressors bind flavonoids which cause them to dissociate from the DNA, promoting induction of gene expression, also consistent with YxaH being an MDR pump.

YxaH of Bacillus subtilis


Uncharacterized protein of 445 aas and 10 TMSs

UP of Thermobifida fusca


Uncharacterized protein of 309 aas and 8 TMSs

UP of Streptosporangium roseum


Uncharacterized protein of 392 aas and 10 TMSs

UP of Vibrio halioticol


YeiB of 385 aas and 8 - 10 TMSs with a C-terminal DUF418 domain. It is encoded within an operon: yeiB-folE where FolE is GTP cyclohydrolase I, the first enzyme in the biosynthesis of tetrahydrofolic acid (El Yacoubi et al. 2006). Therefore YeiB could be a transporter of a derivative in the folate biosynthetic pathway (see also TC# 9.B.169.1.1).

YeiB of E. coli


Uncharacterized protein of 421 aas and 8 TMSs.

UP of Cellulomonas fimi


Uncharacterized protein of 417 aas and 10 TMSs

UP of Sanguibacter keddieii


Uncharacterized protein of 361 aas and 10 TMSs.

UP of Psychroflexus torquis


Uncharacterized protein of 383 aas and 9 TMSs

UP of Paenibacillus mucilaginosus


Uncharacterized protein of 468 aas and 10 TMSs.

UP of Terriglobus saanensis


Uncharacterized protein of 432 aas and 10 TMSs

UP of Halobiforma lacisalsi


Uncharacterized protein of 403 aas and 10 TMSs.

UP of Nocardia brasiliensis


TC#NameOrganismal TypeExample

Uncharacterized protein of 381 aas and 11 TMSs

UP of Methanosarcina acetivorans


Uncharacterized protein of 245 aas and 7 TMSs

UP of Methanococcus maripaludis


Uncharacterized protein, putative acy transferase of 376 aas and 11 TMSs

UP of Ignavibacterium album


DUF1624 protein of 260 aas and 8 TMSs.

DUF1624 of Methanobacterium formicicum


Uncharacterized protein of 394 aas and 11 TMSs

UP of Zobellia galactanivorans


DUF1624 domain-containing protein of 389 aas and 12 TMSs in a possible 5 + 5 + 2 TMS arrangement.

DUF1624 domain protein of Moorea sp. SIO2B7


TC#NameOrganismal TypeExample

DUF418 domain-containing transporter of 376 aas and 10 TMSs

UP of Enhygromyxa salina


Uncharacterized protein of 364 aas and 10 TMSs in a 5 + 5 arrangement.

UP of Sorangiineae bacterium


Uncharacterized protein of 400 aas and 10 TMSs in an apparent 3 + 2 + 3 + 2 arrangement.

UP of Chloroflexi bacterium HGW-Chloroflexi-5


DUF418 acyltransferase family protein of 375 aas and 10 TMSs.

DUF418 protein of Lokiarchaeum sp. GC14_75


Uncharacterized acyltransferase family protein of 373 aas and 10 TMSs. similar to its paralogue with TC# 9.B.169.3.4. The two proteins are encoded by two adject genes on the archaeal chromosome.

UP of Lokiarchaeum sp. GC14_75


TC#NameOrganismal TypeExample

Heparana α-glucosaminide N-acetyltransferase, HGSNAT or MEM76.  Of 663 aas and 12 TMSs in a 1 + 1 + 5 + 5 TMS arrangement.  Mutations cause mucopolysaccharidosis 3C (Fan et al. 2006).  This lysosomal acetyltransferase acetylates the non-reducing terminal alpha-glucosamine residue of intralysosomal heparin or heparan sulfate, converting it into a substrate for luminal alpha-N-acetyl glucosaminidase (Durand et al. 2010).


Uncharacterized DUF5009 protein of 373 aas and 10 TMSs in a 5 + 5 arrangement.

UP of Bacteroides cellulosilyticus


Uncharacterized DUF5009 protein of 442 aas and 10 TMSs in a 5 + 5 arrangement.

UP of Mobiluncus mulieris


Uncharacterized DUF3009 protein of 418 aas and 10 TMSs in a 5 + 5 arrangement.

DUF5009 protein of Singulisphaera acidiphila


Uncharacterized but putative heparan-alpha-glucosaminide N-acetyltransferase (annotation) of 395 aas and 10 TMSs.

UP of Pseudoalteromonas lipolytica


DUF5009 domain-containing proteinof 387 aas and 10 TMSs in a 5 + 5 arrangement.

DUF5009 of Prosthecobacter debontii


TC#NameOrganismal TypeExample

Uncharacteerized OpgC-domain containing protein of 425 aas and 10 TMSs.

UP of Candidatus Prometheoarchaeum syntrophicum


Uncharacterized protein of 463 aas and 10 TMSs

UP of Spirochaeta isovalerica


Uncharacterized protein of 488 aas and 10 TMSs.

UP of Candidatus Heimdallarchaeota archaeon AB_125 (marine sediment