Na,K-ATPase from Xenopus laevis kidney and epidermis: ouabain interaction studies
Bollettino Della Societa Italiana Di Biologia Sperimentale
|December 15, 1982
Abstract:
A satisfactory purification from Xenopus laevis epidermis is presented. Ki and Kd values for the ouabain-enzyme interaction have been evaluated. Both parameters appear very low, as compared with those demonstrated in other anurans. Very low digitalis-like compound level was demonstrated in Xenopus; on the contrary in Bufo, in which these substances play a defensive role, it is very high. Our results strengthen the hypothesis of a physiological action of such compounds in regulating enzyme-driven Na+/K+ exchanges.
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