The E1/E2-preference of gastric H,K-ATPase mutants.
Gastric H,K-ATPase has, in the absence of ATP and added ions, a preference for the E(2) conformation. Mutations in the cation-binding pocket often result in a preference for the E(1)-conformation. This can be paralleled by the occurrence of K(+)-independent ATPase activity. These two phenomena could be separated by combined mutagenesis of several residues in and around the cation-binding pocket. Models of the three-dimensional structure of H,K-ATPase visualize the relationship between the E(1)/E(2) preference and the structure.
De Pont
Jan Joep H H M
JJ
Department of Biochemistry, Nijmegen Center for Molecular Life Sciences, University of Nijmegen, the Netherlands. J.dePont@ncmls.kun.nl
Swarts
Herman G P
HG
Willems
Peter H G M
PH
Koenderink
Jan B
JB
D019943:Amino Acid Substitution; D000818:Animals; D004791:Enzyme Inhibitors / Q000494:pharmacology; D005753:Gastric Mucosa / Q000201:enzymology; D007093:Imidazoles / Q000494:pharmacology; D007700:Kinetics; D016297:Mutagenesis, Site-Directed; D011188:Potassium / Q000378:metabolism; D011487:Protein Conformation; D011994:Recombinant Proteins / Q000737:chemistry / Q000378:metabolism; D000254:Sodium-Potassium-Exchanging ATPase / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism*; D014638:Vanadates / Q000494:pharmacology
D004791:Enzyme Inhibitors; D007093:Imidazoles; D011994:Recombinant Proteins; C035235:Sch 28080; D014638:Vanadates; D000254:Sodium-Potassium-Exchanging ATPase; D011188:Potassium