The effect of inorganic phosphate on the stability of some enzymes

Abstract

In the presence of 5nM-P1, 6-phosphogluconate dehydrogenase from the yeast Candida utilis is more resistant to proteolysis and to the inactivating action of some chemical and physical agents. P1 also protects other enzymes against proteolysis. A hypothesis for the mechanism of the stabilizing action of P1 is advanced.

Crystallographic study of coenzyme, coenzyme analogue and substrate binding in 6-phosphogluconate dehydrogenase: implications for NADP specificity and the enzyme mechanism

“…Inorganic phosphate has been shown to stabilize 6PGDH [20] and to inhibit competitively with both coenzyme and substrate with inhibition constants (K i ) in the 4-8 mM range. Oxaloacetate, citrate, sulphate (K i 8mM) and pyrophosphate also inhibit [18].…”

Galactose Oxidase Immobilized on Silica in an Analytical Determination of Galactose-containing Carbohydrates

“…It is quite possible that in the case of GalO adsorption on the silica surface, high conformational stability of the biocatalyst (and thus its high activity) was available. A similar, but more significant effect was observed 19 during incubation of the enzyme in the phosphate buffer due to the formation of phosphate "bridges", which also stabilize the conformation of the protein molecules.…”

Non-enzymic protein phosphorylation. Phosphorylation of 6-phosphogluconate dehydrogenase by acyl phosphates

“…The untreated and phosphorylated enzymes were inactivated, by the described procedure, with periodate (Rippa et al, 1978a), 5,5'-dithiobis-(2-nitrobenzoate) (Rippa et al, 1978b), pyridoxal 5'-phosphate (Rippa et al, 1967), diethylpyroc\arbonate (Rippa et al, 1972), and trypsin (Rippa et al, 1981).…”