8-Glucosidases enzyme affinity

Acarbose Precose) is an ohgosaccharide derivative that has a higher affinity for the a- glucosidase enzymes than do other dietary oUgosaccharides. Systemic absorption of acarbose is very low ( 2%), with most being broken down in the intestine to several metabolites. About half of the orally administered acarbose is excreted unchanged in the feces, while the remainder, some of which is systemically absorbed, is renally excreted. Acarbose may be associated with hepatotoxicity in rare instances. 

Changed kinetic parameters of the enzyme may be one of the reasons leading to the increased aryl-3-glucosidase in the mutant ATG-5. When comparing K and V in the wild and the mutant strain at 50 C (Table 1) it was shown that So h parameters changed. The enzyme affinity to the substrate increased roughly 2.5-fold in the mutant strain, however, V simultaneously decreased. Thus, it can be assumed that qualitative changes... 

K. M. Osiecki-Newman, D. Fabbro, T. Dinur, S. Boas, S. Gatt, G. Legler, R. J. Desnick, and G. A. Grabowski, Human acid p-glucosidase Affinity purification of the normal placental and Gaucher disease splenic enzymes on N-alkyl-deoxynojirimycin-sepharose, Enzyme, 35 (1986) 147-153. 

Le Traon-Masson, M.-P. and Pellerin, P., Purification and characterization of two P-D-glucosidases from an Aspergillus niger enzyme preparation affinity and specificity toward glucosylated compounds characteristic of the processing of fruits. Enzyme Microb. Technol 22, 374, 1998. 

Since essentially all of the protein in the cellulose-grown culture or the sophorose-incubation mixture can be accounted for by the three principal proteins and the / -glucosidase, it seems reasonable to conclude that the multiplicity of enzymes seen after several days of culture growth are caused by degradation. This may be attributable either to inherent instability (3) or to the presence of hydrolytic enzymes (16). There seems to be no evidence for the Ci enzyme as a nonhydrolytic or affinity factor, since all known enzymes of the system are hydrolytic. That the sophorose-stimulated system (with no possible loss of the Ci ... 

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