Glucose-6-phosphatase stability

The effects of temperature both on the stability of the enzyme (26, 37, 41, 46) and on the catalytic reaction itself (46, 112) have been studied. The enzyme is considerably more labile to mild heating in the absence of substrates than is microsomal acid phosphatase (26, 37, 4U 46)-Glucose-6-P (26, 136), P, (26), glucose (136), PP, (119, 136), and various amino acids (136) protect to some degree against thermal inactivation as do certain metal chelators which inhibit the reaction (120). 

Glucose-6-phosphatase regulating protein (M.W. 21,000), which stabilizes the activity of glucose-6-phosphatase ... 

In addition to altering the maximum potential activity of glucose-6-phosphatase, treatment with phospholipase A leads to a reversible increase in the affinity of this enzyme for glucose-6-phosphate (G-6-P), and to differential stabilities in the PPj-glucose phosphotransferase activity and in the PPi- and glucose-6-P-phosphohydrolase activities of the enzyme. All of these activities (equations la, lb, 2, and 3, below) have been shown to be common to one enzyme (cf., Nordlie and Arion, 1964). 

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