Modification of the pH dependence of animal and plant transport ATPases by sulfated polysaccharides.
The effects of heparin and dextran sulfate 8,000 on two isoforms of the sarco/endoplasmic reticulum Ca(2+)-ATPase of different animal tissues and on the corn root H(+)-ATPase were examined. In the absence of sulfated polysaccharides the pH profile's of the three transport ATPases were quite different, but after the addition of heparin or dextran sulfate 8,000 the pH profiles of the three enzymes became similar, all showed maximal activity at pH 7.0. Potassium and sodium antagonized the effects of sulfated polysaccharides on the three transport ATPases, but the antagonism was considerably reduced at acidic pH values.
Rocha
J B
JB
Departamento de Quimica, Universidade Federal de Santa Maria, Brazil.
Landeira-Fernandez
A M
AM
de Meis
L
L
D000818:Animals; D001692:Biological Transport; D001921:Brain / Q000201:enzymology; D000252:Calcium-Transporting ATPases / Q000187:drug effects* / Q000378:metabolism; D016264:Dextran Sulfate / Q000494:pharmacology*; D006493:Heparin / Q000494:pharmacology*; D006863:Hydrogen-Ion Concentration; D018656:Muscle Fibers, Fast-Twitch / Q000201:enzymology; D018517:Plant Roots / Q000201:enzymology; D006180:Proton-Translocating ATPases / Q000187:drug effects* / Q000378:metabolism; D011817:Rabbits; D012519:Sarcoplasmic Reticulum / Q000201:enzymology; D013463:Sulfuric Acid Esters / Q000494:pharmacology; D003313:Zea mays / Q000201:enzymology
D013463:Sulfuric Acid Esters; D006493:Heparin; D016264:Dextran Sulfate; D006180:Proton-Translocating ATPases; D000252:Calcium-Transporting ATPases