EC Number   |
General Information |
Reference |
|---|
    3.2.1.48 | evolution |
the enzyme belongs to the glycoside hydrolase family 31 (GH31). All GH31 enzymes share a consensus sequence harboring an aspartic acid residue as a catalytic nucleophile |
751091 |
| 3.2.1.48 | malfunction |
congenital sucrase-isomaltase deficiency is a rare genetic form of disaccharide malabsorption characterised by diarrhoea, abdominal pain and bloating, which are features common to irritable bowel syndrome. Sucrase-isomaltase gene variants are tested for their potential relevance in irritable bowel syndrome. Sucrase-isomaltase gene variants coding for disaccharidases with defective or reduced enzymatic activity predispose to irritable bowel syndrome |
750717 |
| 3.2.1.48 | malfunction |
reduced or absent enzymatic levels of sucrase-isomaltase (SI) can lead to carbohydrate malabsorption with gastrointestinal symptoms, such as osmotic diarrhea, bloating, flatulence, and vomiting. SI deficiencies can occur primarily as a consequence of mutations in the coding region of the SI gene, referred to as congenital sucrase-isomaltase deficiency (CSID). Deleterious mutations are associated with alterations in the intracellular trafficking, functional deficits, and missorting of SI. Secondary SI deficiencies, on the other hand, arise collaterally to other organ pathologies in the intestine, in which the integrity and/or the normal physiology of the intestinal epithelium is severely affected, for example in intestinal ulcers or infections and inflammatory bowel disease. Inactivation of one subunit of SI by mutagenesis is not paralleled by loss or reduction in the functional capacity of the other |
751091 |
| 3.2.1.48 | metabolism |
sucrase-isomaltase (SI) catalyzes the final step of carbohydrate digestion by breaking disaccharides and oligosaccharides to absorbable monosaccharides |
751091 |
| 3.2.1.48 | more |
enzyme structure-function analysis, overview |
751091 |
| 3.2.1.48 | physiological function |
core2 1,6-N-acetylglucosaminyltransferase-2 knockdown significantly reduces cell surface expression of sucrase isomaltase and dipeptidyl peptidase-IV in Caco-2 cells. Overexpression of the core3 structure in HT-29 cells attenuates cell surface expression of both enzymes |
715559 |
| 3.2.1.48 | physiological function |
involved in processing alpha-1,6-glucans. Pullulan is likely degraded extracellularly by an amylopullulanase and further hydrolyzed by the PF0132 protein after intracellular transport |
721339 |
| 3.2.1.48 | physiological function |
promastigotes take up sucrose via a H+-sucrose symport system and, on entering the cell, the sucrose is hydrolysed to its component monosaccharides by intracellular sucrase |
-, 715207 |
| 3.2.1.48 | physiological function |
sucrase-isomaltase (SI, EC 3.2.1.48 and 3.2.1.10) is an intestinal membrane-associated alpha-glucosidase that breaks down di- and oligosaccharides to absorbable monosaccharides. The enzyme has two homologous functional subunits (sucrase and isomaltase) that both belong to the glycoside hydrolase family 31 (GH31) and differ in substrate specificity. Glucose product inhibition regulates the activities of both SI subunits |
751091 |
| 3.2.1.48 | physiological function |
the fully glycosylated mature form of sucrase isomaltase is decreased in core2 1,6-N-acetylglucosaminyltransferase-2 knock-out mice but not in core2 N-acetylglucosaminyltransferase-3 nulls. Expression of sucrase isomaltase and dipeptidyl peptidase-IV is dramatically reduced in core2 1,6-N-acetylglucosaminyltransferase-1-3 triple knock-out mice. Goblet cells in the upper part of the crypt show impaired maturation in the core2 O-glycan-deficient mice |
715559 |
