Figure 5: a) Structural alignment of MthK and the modeled MjK2. The transmembrane domain of MjK2 (green) modeled based on template 3LDC (1.45 A) using Swiss Model software [29-31] and aligned with the MthK structure (blue; 3LDC) obtained from www.pdb.org. The potassium-selectivity filter, F39 (MjK2) and W52 (MthK) are illustrated using sticks, whereas potassium is given as spherical marbles. The amino acid sequence alignment is shown below. b) Structural alignment of the RCK domains of MthK, hslo1, hslo3 and modeled MjK2. The RCK domain of MjK2 (orange) modeled based on the template lnqE (3.30 A) using Swiss Model software [29-31] aligned with the gating rings of MthK (magenta; 3RBZ (8)), hslo1 (yellow; 3NAF (25)) and hslo3 (pale blue; 3U6N (26)) obtained from www.pdb.org. The structures were edited and visualized using Pymol software. The position D184 in MthK is indicated by a red line.