Reconstitution of the Na+K+ pump of Ehrlich ascites tumor and enhancement of efficiency by quercetin.
Plasma membranes from Ehrlich ascites tumor cells were solubilized by octylglucoside in the presence of phospholipids. The Na+K+-ATPase was purified from this extract by adsorption and elution from thio-Seph-arose 4B. The enzyme (specific activity, 7 mumoles of ATP hydrolyzed min-1 mg of protein -1) was reconstituted into liposomes by the octyglucoside dilution procedure. An ATP-dependent Na+ influx with low efficiency was observed. On addition of appropriate amounts of quercetin, the Na+ flux/ATP hydrolysis ratio was increased from 0.4 to 1.4.
D000818:Animals; D002286:Carcinoma, Ehrlich Tumor / Q000201:enzymology*; D002462:Cell Membrane / Q000201:enzymology; D003840:Deoxycholic Acid / Q000494:pharmacology; D005419:Flavonoids / Q000494:pharmacology*; D005960:Glucosides / Q000494:pharmacology; D007700:Kinetics; D051379:Mice; D011794:Quercetin / Q000494:pharmacology*; D000254:Sodium-Potassium-Exchanging ATPase / Q000302:isolation & purification / Q000378:metabolism*
D005419:Flavonoids; D005960:Glucosides; D003840:Deoxycholic Acid; C018619:octyl-beta-D-glucoside; D011794:Quercetin; D000254:Sodium-Potassium-Exchanging ATPase