Fig 2. Structure of AdiC.
a. Sequence of AdiC aligned with two other E. coli virtual proton pump exchangers in the APC superfamily: PotE (ornithine/putrescine) and CadB (lysine/cadaverine). The five TMs lining the central cavity are highlighted, with matched colors representing helices paired by inverse repeat. Conserved aromatic residues discussed in the text are indicated in red. b. Ribbon diagrams of homodimer viewed from membrane, extracellular side up (upper panel) and from extracellular solution (lower panel), with Y93, W202, W293 side chains indicated (pink sticks). N- and C-termini indicated by blue, red spheres. TM 11,12 are indicated as darker hue in each subunit.