BINDING OF RIBULOSE 1,5-BISPHOSPHATE TO THE NONCATALYTIC SITES OF RIBULOSE 1,5-BISPHOSPHATE CARBOXYLASE OXYGENASE AND ITS METABOLIC IMPLICATIONS/

This is the first report showing that ribulose bisphosphate carboxylas e/oxygenase has the non-catalytic sites to bind ribulose bisphosphate (RuBP). A plot of the binding number against the RuBP concentration in the equilibrium binding assay gave a bumpy curve with an intermediate plateau at 0.3 to 0.5 mM RuBP. The binding was saturated with 1.5 mM RuBP. The concentrations of free and binding forms of RuBP and the fun ctioning forms of the enzyme in chloroplasts could be predicted using the kinetic data of the binding.