Recognition Properties of Processing α‐Glucosidase I and α‐Glucosidase II
摘要:
All four possible monodeoxy derivatives of p-nitrophenyl alpha-D-glucopyranoside (PNP Glc) and 1-amino-2,6-anhydro-1-deOXY-D-glycero-D-ido-heptitol derivatives were prepared and used as substrates and inhibitors of rat liver processing alpha-glucosidases. alpha-Glucosidase II hydrolyzed the 2-deoxy derivative of PNP Glc (1); the hydrolysis of 1 was more rapid than that of PNP Glc. These results indicate that the presence of a C-2 hydroxyl group is not essential for the action of alpha-glucosidase II. In contrast, PNP Glc and all of the deoxy derivatives of PNP Glc 1-4 inhibited alpha-glucosidase I. These results indicate that alpha-glucosidase I does not necessarily need all of the hydroxyl groups of the glycon moiety for binding to the enzyme. 2,6-Anhydro-1-benzamide-D-glycero-D-ido-heptitol (11), with a terminal phenyl group, inhibited a-glucosidase I and a-glucosidase II. Both alpha-glucosidase I and II showed the same aglycon specificities. When probes 5-12 were assayed for their ability to inhibit processing by a-glucosidases at the cellular level, no effects on glycoprotein processing were observed.
Recognition Properties of Processing α‐Glucosidase I and α‐Glucosidase II
摘要:
All four possible monodeoxy derivatives of p-nitrophenyl alpha-D-glucopyranoside (PNP Glc) and 1-amino-2,6-anhydro-1-deOXY-D-glycero-D-ido-heptitol derivatives were prepared and used as substrates and inhibitors of rat liver processing alpha-glucosidases. alpha-Glucosidase II hydrolyzed the 2-deoxy derivative of PNP Glc (1); the hydrolysis of 1 was more rapid than that of PNP Glc. These results indicate that the presence of a C-2 hydroxyl group is not essential for the action of alpha-glucosidase II. In contrast, PNP Glc and all of the deoxy derivatives of PNP Glc 1-4 inhibited alpha-glucosidase I. These results indicate that alpha-glucosidase I does not necessarily need all of the hydroxyl groups of the glycon moiety for binding to the enzyme. 2,6-Anhydro-1-benzamide-D-glycero-D-ido-heptitol (11), with a terminal phenyl group, inhibited a-glucosidase I and a-glucosidase II. Both alpha-glucosidase I and II showed the same aglycon specificities. When probes 5-12 were assayed for their ability to inhibit processing by a-glucosidases at the cellular level, no effects on glycoprotein processing were observed.