A K+ transport ATPase in Escherichia coli.
A K+ -stimulated ATPase in membranes of Escherichia coli has been identified as an activity of the Kdp system, and ATP-driven K+ transport system. Three characteristics support association of the ATPase with the Kdp system: (i) ATPase and Kdp transport are both repressed by growth in media containing high concentrations of K+; (ii) the ATPase and Kdp system accept only K+ as substrate, neither requires Na+ nor accepts Rb+ as a substrate; (iii) the affinity of the ATPase and that of th Kdp system for K+ is similar and is altered by mutations in the structural genes of the Kdp system. Discovery of an ATPase associated with a bacterial transport system suggests functional similarities with the ATP-driven transport systems of animal cells.
D001693:Biological Transport, Active; D002413:Cations, Divalent; D002462:Cell Membrane / Q000201:enzymology; D004926:Escherichia coli / Q000378:metabolism*; D007700:Kinetics; D009154:Mutation; D011188:Potassium / Q000378:metabolism*; D000254:Sodium-Potassium-Exchanging ATPase / Q000378:metabolism*; D013045:Species Specificity
D002413:Cations, Divalent; D000254:Sodium-Potassium-Exchanging ATPase; D011188:Potassium