Yeast Pyruvate Kinase
نویسندگان
چکیده
The kinetic properties of purified yeast pyruvate kinase were investigated. The enzyme showed cooperative kinetics toward the essential activating monovalent cations K+ and NH4+, Mg2+, and phosphoenolpyruvate. Fructose 1,6diphosphate, which yielded homotropic cooperative kinetics and did not affect maximal velocity, transformed the sigmoidal kinetics of Kf and NH4+, Mgz+, and phosphoenolpyruvate to hyperbolic and lowered the apparent M, for each variable. Adenosine diphosphate, however, exhibited no cooperativity and was relatively unaffected by fructose 1,6diphosphate. The enzyme displayed a complex velocity dependence on pH.
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