9.B.15 The 4 TMS YbhQ (YbhQ) Family
YbhQ of E. coli (TC# 9.B.15.1.1) is a 4 TMS protein with N- and C-termini on the inside (Daley et al., 2005). Some annotations suggest YbhQ is a heme/copper-type cytochrome/quinol oxidase subunit, but this could not be substantiated. Homologues are only found in E. coli and other closely related γ-proteobacteria. The 4 TMSs probably arose by duplication of a 2 TMS-encoding genetic element, but this suggestion needs to be confirmed.
A second family (TC# 9.B.15.2) with 4 TMSs and similar sizes is the DUF1772 family with many members from Actinobacteria. It is not established that these two subfamilies of 4 TMS proteins are related.
4 TMS protein of 128 aas, YbhQ
YbhQ of Candidatus Pantoea carbekii
Uncharacterized protein of 150 aas and 4 TMSs.
UP of Mycobacterium avium
Uncharacterized protein of 202 aas and 4 TMSs
UP of Geodermatophilus obscurus
Uncharacterized protein of 181 aas and 4 - 5 TMSs.
UP of Bdellovibrio bacteriovorus
Uncharacterized protein of the DUF1772 family of 148 aas and 4 TMSs.
UP of Streptomyces coelicolor
Uncharacterized protein of the DUF1772 family of 153 aas and 4 TMSs
UP of Mesorhizobium sp. L103C119B0
Uncharacterized protein of 147 aas and 4 TMSs
UP of Methylobacterium populi
Uncharacterized protein of 154 aas and 4 TMSs.
UP of Verrucosispora maris
Uncharacterized DUF1772 protein of 147 aas and 4 TMSs
UP of Coccomyxa subellipsoidea
Uncharacterized protein of 172 aas and 4 TMSs
UP of Thermomonospora curvata
Uncharacterized protein of 151 aas and 4 TMSs
UP of Actinoplanes sp. N902-109
Uncharacterized protein of 134 aas and 4 TMSs.
UP of Rhodopseudomonas palustris