10.7554/eLife.23644.010Figure 2—figure supplement 4.Stereo view of domain 3 with the upper part of the β-barrel and the new helix-turn-helix motif (HTH) that forms the α-barrel inside the pore.The new helix α3a (red) from the neighboring monomer is on the right. Hydrophobic residues at the interface between the β-sheet and HTH and intermolecular interactions to the next helix α3a are shown as stick models. The map is contoured at 6.5 and 8 σ.DOI: http://dx.doi.org/10.7554/eLife.23644.010