Phosphorylation of Ca2+-ATPase by inorganic phosphate in water-organic solvent media: dielectric constant and solvent hydrophobicity contribution.

نویسندگان

  • A de Souza Otero
  • L de Meis
چکیده

The effect of organic solvents on the phosphorylation of the Ca2+-dependent ATPase of sarcoplasmic reticulum by inorganic phosphate in the absence of a calcium gradient was investigated. Kinetic analysis of the reaction in water and water-organic solvent media according to a bireactant scheme shows no correlation between changes in kinetic parameters and the dielectric constant of the mixed solvents. The pronounced increase in equilibrium levels of phosphoenzyme in water-solvent mixtures is attributed to changes in the water activity of the medium.

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عنوان ژورنال:
  • Zeitschrift fur Naturforschung. Section C, Biosciences

دوره 37 5-6  شماره 

صفحات  -

تاریخ انتشار 1982