Abstract
Phospoenolpyruvate carboxylase isolated from Panicum maximum Jacq. leaf presented a hysteretic behcaviour that resulted in a kinetical lag in the reaction progress curve. This lag depended on the concentration of enzyme, total phospoenolpyruvate (PEP) and total Mg2+. Through an analysis of these dependencies it is suggested that the hysteresis is due to an association-dissociation process, influenced by union, to one form of the enzyme, of more than one of the three possible ligands: free Mg2+, free PEP or PEP-Mg2+ complex. The partially purified enzyme showed, during steady state, a Michaelis-Mentin kinetics for PEP and Mg2+ (total concentration) and pH optima between 7.8 and 8.2.
Original language | English |
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Pages (from-to) | 317-320 |
Journal | Photosynthetica |
Volume | 28 |
Issue number | 2 |
Publication status | Published - 1993 |