. Author manuscript; available in PMC: 2013 Mar 1.

Published in final edited form as: Biochim Biophys Acta. 2011 Nov 4;1818(3):592–600. doi: 10.1016/j.bbamem.2011.10.029

Table 2.

The ratios of Na⁺ to K⁺ current (J_Na⁺ / J_K⁺), Na⁺ to K⁺ occupancy (N_Na⁺ / N_K⁺) in the filter and in the entire pore for different pore radii (R_f). Occupancy is the average number of ions whose centers are in the filter (| z |< 0.5 nm) or in the whole channel (| z |<1 nm). In all cases, there was 150 mM NaCl in the left bath and 150 mM KCl in the right bath, the physiological separation of ions. The amino acid (aa) space-filled fraction is shown in the last column.

Ratios of Na⁺ to K⁺ currents and occupancy
filter ions	filter radius R_f	J_Na⁺ / J_K⁺	N_Na⁺ / N_K⁺ (filter)	N_Na⁺ / N_K⁺ (channel)	aa space-filled fraction
DEKA (4 O^1/2 +Lys⁺)	0.35 nm	11.12	3.75	1.62	0.156
DEKA	0.3 nm	326	8.39	1.62	0.213
DEKA	0.4 nm	5.04	2.70	1.57	0.120
4 O^1/4− +Lys⁰	0.35 nm	9.86	3.55	1.52	0.156
4 O^1/4−, no Lys	0.35 nm	6.51	2.89	1.55	0.121