Effect of internal or external sucrose additions on pore resistances
| Variant | RT (Control) | RTSuc (Int. sucrose) | RTSuc (Ext. sucrose) | RAccIn | RAccEx | RInnerPore |
| WT | 39 ± 1 | 90 ± 5 | 53 ± 2 | 8.2 ± 0.7 | 2.1 ± 0.4 | 30 ± 1 |
| P475Q | 20 ± 2 | 77 ± 7 | 31 ± 1 | 9.3 ± 1.1 | 1.5 ± 0.3 | 9.3 ± 1.0 |
| P475D | 6.6 ± 0.2 | 16 ± 1 | 19 ± 1 | 1.5 ± 0.5 | 2.0 ± 0.1 | 3.0 ± 0.3 |
| Variant | RT (Control) | RTSuc (Int. sucrose) | RTSuc (Ext. sucrose) | RAccIn | RAccEx | RInnerPore |
| WT | 39 ± 1 | 90 ± 5 | 53 ± 2 | 8.2 ± 0.7 | 2.1 ± 0.4 | 30 ± 1 |
| P475Q | 20 ± 2 | 77 ± 7 | 31 ± 1 | 9.3 ± 1.1 | 1.5 ± 0.3 | 9.3 ± 1.0 |
| P475D | 6.6 ± 0.2 | 16 ± 1 | 19 ± 1 | 1.5 ± 0.5 | 2.0 ± 0.1 | 3.0 ± 0.3 |
RT is the resistance measured in 100 mM of symmetric K+. RTSuc was measured with 2 M sucrose added unilaterally to either the internal or external side. Resistances were measured by estimating the slope conductance crossing the plot’s origin as in Figs. 1 and S2. RAccIn and RAccEx are the access resistances of the internal and external entrances, respectively, whereas RInnerPore is the resistance of the pore region that is not sucrose accessible. RAccIn, RAccEx, and RInnerPore were calculated from Eq. 2, assuming a 7.14-fold increment in the resistivity of the solution after the addition of 2 M sucrose (Brelidze and Magleby, 2005). All estimations are from a minimum of three individual patches. Resistances are in GΩ.