ATP synthesis by the (Na+ + K+)-ATPase in the absence of an ionic gradient. Effects of organic solvent.
A 200-fold decrease in the Pi concentration required for half-maximal phosphorylation of the (Na+ + K+)-ATPase is observed when 40% (v/v) dimethyl sulfoxide is added to the assay medium. The phosphoenzyme formed in the presence of dimethyl sulfoxide is able to transfer its phosphate to to form ATP when concentrations of organic solvent and of Na+, and is inhibited by ouabain.
de Moraes
V L
VL
Departamento de Bioquimica, Universidade Federal do Rio de Janeiro, Ilha do Fundao, Brazil.
de Meis
L
L
D000255:Adenosine Triphosphate / Q000096:biosynthesis*; D000818:Animals; D007668:Kidney / Q000201:enzymology; D007700:Kinetics; D010710:Phosphates / Q000378:metabolism*; D010766:Phosphorylation; D012756:Sheep; D000254:Sodium-Potassium-Exchanging ATPase / Q000378:metabolism*; D012997:Solvents
D010710:Phosphates; D012997:Solvents; D000255:Adenosine Triphosphate; D000254:Sodium-Potassium-Exchanging ATPase