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Table 9 Kinetic equation and factors for cytosolic glucan phosphorylase.

From: Kinetic modeling and exploratory numerical simulation of chloroplastic starch degradation

Haldane relation
Equilibrium constant from substrate and product Gibbs free energies1
Gibbs reference free energy corrected for ionic strength [56]
V fmax ; [CGP] = 2 μM
K MA 2 2.1 mM[57]
K iA 2 3.8 mM[57]
K MB 2 5.9 mM[57]
K MP 2 2.0 mM[57]
K iP 2 3.1 mM[57]
K MQ 3.8 mM[57]
  1. Concentrations A = glucosylated arabinogalactan, B = phosphate, P = glucose-1-phosphate, and Q = arabinogalactan.
  2. 1 is the standard Gibbs free energy of formation of species i with charge z i at 298.15 °K and at a cytosolic ionic strength (I) of 0.15 M. The (I = 0) values for A (glucosylated arabinogalactan) and Q (arabinogalactan) are assumed to be equal to the corresponding values for Glycogen(n) and Glycogen(n-1) respectively tabulated in Ref. [58]. The (I = 0) values for B (phosphate) and P (glucose-1-phosphate) are tabulated in Ref. [56].
  3. 2 K mA , K iA , and K MB values are taken from the polysaccharide degradation reaction catalyzed by potato phosphorylase, with A = amylopectin and B = phosphate. The K MP , K iP , and K MQ values are taken from the polysaccharide synthesis reaction catalyzed by potato phosphorylase, with P = glucose 1-phosphate and Q = amylopectin.