Amino acid substitutions in putative selectivity filter regions III and IV in KdpA alter ion selectivity of the KdpFABC complex from Escherichia coli.
When grown under conditions of potassium limitation or high osmolality, Escherichia coli synthesizes the K(+)-translocating KdpFABC complex. The KdpA subunit, which has sequence homology to potassium channels of the KcsA type, has been shown to be important for potassium binding and transport. Replacement of the glycine residues in KdpA at positions 345 and 470, members of putative selectivity filter regions III and IV, alters the ion selectivity of the KdpFABC complex.
Abteilung Mikrobiologie, Fachbereich Biologie/Chemie, Universität Osnabrück, D-49076 Osnabrueck, Germany.
Jessica
J
Bertrand
Karlheinz
K
Altendorf
Marc
M
Bramkamp
D000251:Adenosine Triphosphatases / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism*; D019943:Amino Acid Substitution; D027682:Cation Transport Proteins / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism*; D002414:Cations, Monovalent / Q000378:metabolism*; D004926:Escherichia coli / Q000235:genetics* / Q000378:metabolism*; D029968:Escherichia coli Proteins / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism*; D005798:Genes, Bacterial; D016297:Mutagenesis, Site-Directed; D020125:Mutation, Missense; D011188:Potassium / Q000378:metabolism*; D017434:Protein Structure, Tertiary; D021122:Protein Subunits / Q000235:genetics / Q000378:metabolism; D013379:Substrate Specificity
D027682:Cation Transport Proteins; D002414:Cations, Monovalent; D029968:Escherichia coli Proteins; D021122:Protein Subunits; D000251:Adenosine Triphosphatases; C058166:potassium translocating Kdp-ATPase, E coli; D011188:Potassium