Adenosine triphosphatase assay

In some experiments concerned with the mechanism by which tryptophan acted to improve hepatic protein synthesis after toxic injury, the ability of tryptophan to stimulate hepatic mRNA synthesis, nucleocytoplasmic translocation of RNA in vitro, and nuclear envelope nucleoside triphosphatase activity after hepatotoxic injury was measured.188 Nucleoside triphosphatase (Mg2+-dependent adenosine triphosphatase, EC 3.6.1.3.1) was assayed since it is present in mammalian liver nuclear envelopes,224 and there is evidence that this enzyme is involved in nucleocytoplasmic translocation of RNA.221 All of these parameters were elevated significantly by tryptophan after agents such as actinomycin D, cordycepin, ethionine, puromycin, and hypertonic NaCl demonstrated a curative effect by tryptophan, but not after tryptophan following CC14, NaF, and sparsomycin demonstrated no improvement with tryptophan. These findings emphasized the importance of the role that tryptophan plays in stimulating the availability of cytoplasmic... 

Enzymes, such as 7-GTP, glucose-6-phosphate (G-6-Pase), and canalicular adenosine triphosphatase (ATPase) have been generally used as markers for assaying initiated cell populations in liver carcinogenesis [15]. In order to confirm the essential similarity of foci induced by DEN plus ABA to those observed after DEN alone, a comparison of histochemical characteristics was made. The foci induced by DEN plus PH, typically showing positive for 7-GTP and periodic acid Schiff stain and negative for G-6-Pase and ATPase. 

Both compounds were reversible inhibitors of (Na+ K ) adenosine-triphosphatase when assayed in dim light. The KiS were 1.3 itM for DAMN-cymarin and 0.9 joM for CM-cymarin. 

Kasamo K. Purification and properties of the plasma membrane H -translocating adenosine triphosphatase of Phaseolus munqo L. roots. Plant Physiol. 1986 80 818-824. Peterson GL. A simplification of the protein assay method of Lowry et al. which is more generally applicable. Anal. Biochem. 1977 83 346-356. 

Lanzetta PA, Alvarez LJ, Reinach PS, and Candia OA (1979) An improved assay for nanomole amounts of inorganic phosphate. Anal, Biochem, 100, 95-97, Sabnis DD, Gordon M, and Galston AW (1970) Localization of adenosine triphosphatase activity on the chloroplast envelope in tendrils of Pisum sativum. Plant Physiol, 45, 25-32,... 

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