A calorimetric study of the interaction of ATP with rabbit muscle phosphofructokinase.
Journal Article (Journal Article)
The heat of interaction of ATP with phosphofructokinase from rabbit muscle was determined at 25 degrees C in 0.1 M potassium phosphate, pH 7.0 and 8.0. The limiting value of the enthalpy change at high ATP concentrations was found to be -11.5 kcal mol of enzyme polypeptide chains. Since phosphate and imidazole have very different heats of ionization (+0.8 and +7.5 kcal/mol, respectively), this suggests that the binding of at least two protons to the enzyme occurs concomitantly with the binding of ATP at the regulatory site.
- Wolfman, NM; Hammes, GG
- December 25, 1979
Volume / Issue
- 254 / 24
Start / End Page
- 12289 - 12290
International Standard Serial Number (ISSN)
- United States