Fig. 2.

Transport kinetics. (A) Snapshot from the AQP0_J⁴ simulation. Only residues 128–179 (helices IV and V and loop D, green), the B and E half helices (gray), and the two nonhelical repeats (gray) are shown. (B) Calculated osmotic permeability constant, p_f. Means and standard errors were computed among the monomers in each simulation. The abscissa represents cumulative simulation time included in the p_f calculation. The experimental p_f value is 2.5 ± 0.4 (9). (C) Cumulative permeation events (per monomer in either direction). Linear regression to these data yielded p_d = 1.1 for AQP0_NJ⁴, p_d = 1.2 for AQP0_J⁴, and p_d = 1.4 for AQP0_J⁸, consistent with the values in Table 1.