Enzymatic activity of "high-mannose" glycosylated forms of intestinal microvillar hydrolases.
The "high-mannose" glycosylated forms of aminopeptidase N (EC 3.4.11.2), maltase-glucoamylase (EC 3.2.1.20), and sucrase-isomaltase (EC 3.2.1.48, EC 3.2.1.10) have been purified. The high-mannose glycosylated form of sucrase-isomaltase was found to have a lower specific activity than the complex glycosylated form, whereas no difference was observed for the two other enzymes. The change in glycosylation from high-mannose to complex form thus seems to be of importance for the enzymatic activity of sucrase-isomaltase either by direct structural involvement or by a general stabilization effect on the protein conformation.
Sjöström
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Norén
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Danielsen
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D000626:Aminopeptidases / Q000302:isolation & purification*; D000818:Animals; D018826:CD13 Antigens; D005959:Glucosidases / Q000302:isolation & purification*; D007413:Intestinal Mucosa / Q000201:enzymology*; D008358:Mannose / Q000032:analysis; D008871:Microvilli / Q000201:enzymology; D009097:Multienzyme Complexes / Q000302:isolation & purification*; D013394:Sucrase-Isomaltase Complex / Q000302:isolation & purification*; D013552:Swine; D000520:alpha-Glucosidases / Q000302:isolation & purification*
D009097:Multienzyme Complexes; D005959:Glucosidases; D013394:Sucrase-Isomaltase Complex; D000520:alpha-Glucosidases; D000626:Aminopeptidases; D018826:CD13 Antigens; D008358:Mannose