Inhibition by saccharin of glucose-6-phosphatase: effects of alloxan in vivo and deoxycholate in vitro
Department or Administrative Unit
Inhibition by saccharin of rat liver glucose-6-phosphatase (EC 188.8.131.52) generally decreased as the pH increased in the range pH 4–8. This pattern was exhibited by homogenates from control and alloxan-treated animals assayed each in the absence and presence of 0.2% (w/v) deoxycholate. Saccharin inhibited in competitive fashion with respect to glucose-6-phosphate (glucose-6-P). There was a small increase in Km (glucose-6-P) but not Ki (saccharin) values in alloxan-treated rats when assays were conducted in the absence of deoxycholate. In the presence of this detergent there was no significant difference in these kinetic parameters between the alloxan-treated and control groups. Deoxycholate decreased Km (glucose-6-P) and increased Ki (saccharin) values. Calculations using these kinetic parameters indicate that, under usual hepatic glucose-6-P concentrations and relatively high levels of saccharin in liver, the inhibition by saccharin of glucose-6-phosphatase is unlikely to be of major significance in vivo.
Lygre, D. G. (1976). Inhibition by saccharin of glucose-6-phosphatase: effects of alloxan in vivo and deoxycholate in vitro. Canadian Journal of Biochemistry, 54(6), 587–590. https://doi.org/10.1139/o76-087
Canadian Journal of Biochemistry