Isolation and comparative studies of mitochondrial F1-ATPase from rat testis and beef heart.
The isolation and properties of F1-mitochondrial ATPase from rat testis are described. The isolation medium involves a chloroform extraction, and it is suitable even with small amounts of starting material that have a relatively low specific activity as in the case of rat testis submitochondrial particles. The isolated enzyme from rat testis had a specific activity of 30-45 mumol Pi/min/mg protein, which could be increased up to 90 mumol Pi/min/mg protein only in the presence of bicarbonate and maleate. The isolated enzyme represented less than 0.6% of the initial membrane proteins. It exhibited a typical five-band pattern in sodium dodecyl sulfate gel electrophoresis. However, it showed a ratio of subunits alpha:beta higher than the heart enzyme; its significance is unknown. The purified enzyme was cold labile and inhibited by natural ATPase inhibitor protein from bovine heart mitochondria and by dicyclohexylcarbodiimide. The results presented suggest that the low ATPase activity of testis submitochondrial particles is due to a reduced content of the F1-ATPase.
Vázquez-Memije
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ME
Unidad de Investigación Médica en Genética Humana, Centro Médico Nacional, IMSS, México, D.F., México.
Beltrán
C
C
Tuena de Gómez-Puyou
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M
D000255:Adenosine Triphosphate / Q000378:metabolism; D000818:Animals; D002417:Cattle; D004024:Dicyclohexylcarbodiimide / Q000494:pharmacology; D004591:Electrophoresis, Polyacrylamide Gel; D004789:Enzyme Activation; D004791:Enzyme Inhibitors / Q000494:pharmacology; D008297:Male; D008928:Mitochondria / Q000201:enzymology*; D008929:Mitochondria, Heart / Q000201:enzymology; D009928:Organ Specificity; D006180:Proton-Translocating ATPases / Q000037:antagonists & inhibitors / Q000302:isolation & purification* / Q000378:metabolism*; D051381:Rats; D017207:Rats, Sprague-Dawley; D013696:Temperature; D013737:Testis / Q000201:enzymology*
D004791:Enzyme Inhibitors; D004024:Dicyclohexylcarbodiimide; D000255:Adenosine Triphosphate; D006180:Proton-Translocating ATPases