Skip to main content
. 2005 Jun 10;89(3):1744–1759. doi: 10.1529/biophysj.104.058206

FIGURE 2.

FIGURE 2

(a) The QM/MM simulated system, consisting of one GlpF monomer with hydrating (capping) molecules. Nine (QM) water molecules, with the seven central ones within the constriction region, are displayed as solid van der Waals spheres. The remaining QM waters (six more in the cytoplasmic side and six more in the periplasmic side) are not represented. The selectivity filter is displayed with the W48 and F200 side chains in red-licorice representation (omitting H-atoms) and R206 is shown in standard colors. Depicted similarly are side chains of the conserved residues N68/N203 of the NPA motifs in the channel center. The direction of periplasm to cytoplasm is taken along increasing z. (b) AQP characteristic half-membrane spanning repeats with α-helical (69–79(M3), 206–217(M7)) and nonhelical (65–68, 199–205, the conduction pathway) parts rendered in brown and green, respectively. In licorice representation are displayed side chains of R206 and of N68/N203 of the NPA motifs. (c) Schematic hydrogen-bonding structure of the single-file waters and their hydrogen-bonding interactions with the polar groups of channel-lining residues.