Reaction: Hydrolysis of sucrose and maltose by an α-D-glucosidase-type action
Other name(s): sucrose α-glucohydrolase; sucrase (ambiguous); sucrase-isomaltase; intestinal sucrase; SI (gene name)
Systematic name: sucrose-α-D-glucohydrolase
Comments: The enzyme, found in animals, consists of two glycosyl hydrolase 31 domains side by side. The N-terminal domain degrades isomaltose (cf. EC 3.2.1.10, oligo-1,6-glucosidase), while the C-terminal side degrades sucrose. The enzyme recognizes and hydrolyses the α-D-glucoside side of the sucrose molecule (a different enzyme, EC 3.2.1.26, β-fructofuranosidase, recognizes and hydrolyses the fructofuranoside group on the opposite side of sucrose).
Links to other databases: BRENDA, EXPASY, GENE, KEGG, MetaCyc, PDB, CAS registry number: 37288-39-4
References:
1. Conklin, K.A., Yamashiro, K.M. and Gray, G.M. Human intestinal sucrase-isomaltase. Identification of free sucrase and isomaltase and cleavage of the hybrid into active distinct subunits. J. Biol. Chem. 250 (1975) 5735-5741. [PMID: 807575]
2. Hauri, H.-P., Quaroni, A. and Isselbacher, K.J. Biogenesis of intestinal plasma membrane: posttranslational route and cleavage of sucrase-isomaltase. Proc. Natl. Acad. Sci. USA 76 (1979) 5183-5186. [PMID: 291933]
3. Kolinska, J. and Kraml, J. Separation and characterization of sucrose-isomaltase and of glucoamylase of rat intestine. Biochim. Biophys. Acta 284 (1972) 235-247. [PMID: 5073761]
4. Sigrist, H., Ronner, P. and Semenza, G. A hydrophobic form of the small-intestinal sucrase-isomaltase complex. Biochim. Biophys. Acta 406 (1975) 433-446. [PMID: 1182172]
5. Sjöström, H., Norén, O., Christiansen, L., Wacker, H. and Semenza, G. A fully active, two-active-site, single-chain sucrase-isomaltase from pig small intestine. Implications for the biosynthesis of a mammalian integral stalked membrane protein. J. Biol. Chem. 255 (1980) 11332-11338. [PMID: 7002920]
6. Takesue, Y. Purification and properties of rabbit intestinal sucrase. J. Biochem. (Tokyo) 65 (1969) 545-552. [PMID: 5804876]
7. Sim, L., Willemsma, C., Mohan, S., Naim, H.Y., Pinto, B.M. and Rose, D.R. Structural basis for substrate selectivity in human maltase-glucoamylase and sucrase-isomaltase N-terminal domains. J. Biol. Chem. 285 (2010) 17763-17770. [PMID: 20356844]