Subsets of selected sequences are shown from pathogenic bacteria (yellow background), archaeal (gray), slime molds and fungi (blue) and plants (green). Only ecMgtA and stMgtA share more than 90% sequence identity (SI), ecMgtA and the remainder of the bacterial sequences share between 50–55% SI. Archeae, slime mold/fungi and plant share between 33–45% SI. Each selected sequence is shown as a short abbreviation (equivalent to the name given in Figure 1—figure supplement 1) followed by MgtA and corresponding UniProt number. Each black line indicates residues in direct contact with the counter ion, potassium, in the porcine Na+/K+-ATPase. Val 322 and Val 325 contribute with its backbone carbonyl (Morth et al., 2007). The equivalent numbers in ecMgtA are given at the top. Each sequential segment belongs to the four transmembrane helices 4, 5, 6 and 8 as written above. The following coloring scheme is used according to the chemical functionality of the residues: Aliphatic MLIV (light blue); aromatic HFWY (cyan), amide group NQ (purple), hydroxyl group ST (green), negatively charged DE (red), positively charged KR (dark blue), small sidechain AG (orange), P (yellow) and C (light pink).