9.B.426.  The DUF4175/4401 (DUF4175/4401) Family 

This family consists of proteins that probably have 3 TMSs, sometimes with C-terminal hydrophilic domains, and sometimes with N-terminal hydrophilic domains. A few may have up to 6 TMSs, possiblly due to an internal duplication of the 3 TMS unit.  These proteins may (or may not) be distantly related to protein 9.B.143.4.2 which may have 6 or 8 TMSs.


TC#NameOrganismal TypeExample

DUF4175 domain-containing protein of 243 aas and 3 TM

DUF4175 protein of Candidatus Kaiserbacteria bacterium (freshwater metagenome)


DUF4401 domain-containing protein of 288 aas and 3 TMSs.

DUF4401 protein of Candidatus Yonathbacteria bacterium (biofilm metagenome)


Uncharacterized protein of 177 aas and 3 TMSs.

UP of Candidatus Woesebacteria bacterium GW2011_GWD1_38_10 (groundwater metagenome)


Uncharacterized protein of 123 aas and 3 TMSs.

UP of Microgenomates group bacterium


Uncharacterized protein of 245 aas and 3 TMSs.

UP of Candidatus Berkelbacteria bacterium (groundwater metagenome)


Uncharacterized protein of 172 aas and 3 TMSs

UP of Candidatus Methanofastidiosa archaeon (anaerobic digester metagenome)


TC#NameOrganismal TypeExample

Uncharacterized protein of 293 aas with 3 C-terminal TMSs with an N-terminal hydrophilic domain.

UP of Saprospiraceae bacterium (activated sludge metagenome)


Uncharacterized protein of 253 aas and 3 N-terminal TMSs

UP of Candidatus Parcubacteria bacterium (glacier metagenome) [Arenimonas sp.]


Uncharacterized protein of 271 aas and 3, 4, or 5 TMSs.  This first 3 (N-terminal) hydrophobic peaks (TMSs) are large; the fourth is of moderate size, and the fifth is very small.

UP of Candidatus Wolfebacteria bacterium GW2011_GWB1_47_1 (groundwater metagenome)