Internal 6 TMS repeats in 12 TMS proteins. A (left). Hydropathy plot of the ferric iron porter, FutB. Blue lines denote hydropathy; Red lines denote amphipathicity; Orange bars mark transmembrane segments as predicted by HMMTOP. B (right). TMSs 7– 12 of gi163796270 aligned with TMSs 1–6 of gi113476753, yielding a comparison score of 13.7 S.D. with 36.3% similarity and 27.1% identity. The numbers at the beginning of each line refer to the residue numbers in each of the proteins. TMSs are indicated in red lettering. Vertical lines indicate identities; colons indicate close similarities, and periods indicate more distant similarities.