Maltase-glucoamylase and residual isomaltase in sucrose intolerant patients.
Small intestinal biopsies from nine patients with sucrase-isomaltase deficiency (sucrose-intolerance) were analyzed. All patients lacked sucrase activity and three patients had a residual isomaltase activity and a corresponding isomaltase precipitate following immunoelectrophoresis. By polyacrylamide gel electrophoresis in sodium dodecyl sulfate followed by immunoblotting the residual isomaltase appeared as a single polypeptide with molecular weight of approximately 145,000. Maltase-glucoamylase in the biopsies was specifically quantitated by crossed immunoelectrophoresis. One of the patients had an almost total deficiency of maltase-glucoamylase in the biopsy, three patients had a normal amount of maltase-glucoamylase, and five patients constituted an intermediary group. These results indicate that some of the sucrase-isomaltase deficient patients also have a more or less pronounced deficiency of maltase-glucoamylase. The patients constitute an even more heterogeneous group than earlier suggested and should be classified by the amount not only of sucrase and isomaltase but also of maltase-glucoamylase.
D000293:Adolescent; D000328:Adult; D002239:Carbohydrate Metabolism, Inborn Errors / Q000201:enzymology*; D002648:Child; D002675:Child, Preschool; D005087:Glucan 1,4-alpha-Glucosidase / Q000378:metabolism*; D005959:Glucosidases / Q000378:metabolism*; D006026:Glycoside Hydrolases / Q000378:metabolism*; D006801:Humans; D007122:Immunoelectrophoresis; D007123:Immunoelectrophoresis, Two-Dimensional; D007124:Immunoenzyme Techniques; D007583:Jejunum / Q000201:enzymology; D009097:Multienzyme Complexes / Q000172:deficiency*; D009834:Oligo-1,6-Glucosidase / Q000378:metabolism*; D013393:Sucrase / Q000378:metabolism; D013394:Sucrase-Isomaltase Complex / Q000172:deficiency*; D013395:Sucrose / Q000378:metabolism*
D009097:Multienzyme Complexes; D013395:Sucrose; D005959:Glucosidases; D006026:Glycoside Hydrolases; D013394:Sucrase-Isomaltase Complex; D009834:Oligo-1,6-Glucosidase; D005087:Glucan 1,4-alpha-Glucosidase; D013393:Sucrase