Interaction of DnaK with ATP: binding, hydrolysis and Ca+2-stimulated autophosphorylation.
The autophosphorylation of DnaK from Escherichia coli using ATP as phosphate donor is markedly stimulated by Ca+2 and to a lesser degree by Mn+2. Mg+2 and other divalent ions are without effect in this reaction. Lanthanum, an agonist/antagonist of Ca+2, is also effective in stimulating the autophosphorylation. In contrast, Mg+2 but not Ca+2, markedly stimulates the hydrolysis of ATP catalyzed by DnaK. Also at 0 degrees, ATP forms a stable complex with DnaK without hydrolysis that is independent of cations. About 15% of the DnaK in E. coli is associated with membrane vesicles where it also can be phosphorylated in the presence of Ca+2.
Dalie
B L
BL
Roche Institute of Molecular Biology, Roche Research Center, Nutley, NJ 07110.
Skaleris
D A
DA
Köhle
K
K
Weissbach
H
H
Brot
N
N
D000255:Adenosine Triphosphate / Q000378:metabolism*; D000596:Amino Acids / Q000032:analysis; D001426:Bacterial Proteins / Q000378:metabolism*; D002118:Calcium / Q000494:pharmacology*; D002413:Cations, Divalent; D002462:Cell Membrane / Q000378:metabolism; D004533:Egtazic Acid / Q000494:pharmacology; D004926:Escherichia coli / Q000378:metabolism*; D029968:Escherichia coli Proteins; D018840:HSP70 Heat-Shock Proteins; D006360:Heat-Shock Proteins / Q000378:metabolism*; D006868:Hydrolysis; D007700:Kinetics; D007811:Lanthanum / Q000494:pharmacology; D010766:Phosphorylation; D011485:Protein Binding
D000596:Amino Acids; D001426:Bacterial Proteins; D002413:Cations, Divalent; D029968:Escherichia coli Proteins; D018840:HSP70 Heat-Shock Proteins; D006360:Heat-Shock Proteins; D004533:Egtazic Acid; D007811:Lanthanum; D000255:Adenosine Triphosphate; C063842:dnaK protein, E coli; D002118:Calcium