The purification and properties of sucrose-phosphate synthetase from spinach leaves: The involvement of this enzyme and fructose bisphosphatase in the regulation of sucrose biosynthesis

摘要: Abstract The properties of spinach leaf sucrose-phosphate synthetase (EC 2.4.1.14) and cytosolic fructose-1,6-bisphosphatase 3.1.3.11) have been studied. These two enzymes considered to be important in the control sucrose synthesis. Sucrose-phosphate from tissue has not studied detail previously we report a technique for purifying this enzyme 50-fold by chromatography on AH-Sepharose 4B. This method frees contaminants which interfere with assay procedures little or no loss activity. partially purified K m UDP-glucose 7.1 fructose 6-phosphate 0.8 . Fructose 1,6-bisphosphate, inorganic phosphate UDP are strong inhibitors. inhibition patterns these suggest that operates either an ordered bi-bi Theorell-Chance mechanism. Partially is only inhibited AMP as reported, but also UDP. From our observations, conclude biosynthesis indeed controlled through it appears rate synthesis largely dependent upon supply triose ATP chloroplast.