Alpha-glucosidase, glycosyl hydrolase family GH31 [Carbohydrate transport and metabolism].

Glycosyl hydrolases family 31. Glycosyl hydrolases are key enzymes of carbohydrate metabolism. Family 31 comprises of enzymes that are, or similar to, alpha- galactosidases.

neutral alpha-glucosidase C, neutral alpha-glucosidase AB. This subgroup includes the closely related glycosyl hydrolase family 31 (GH31) isozymes, neutral alpha-glucosidase C (GANC) and the alpha subunit of heterodimeric neutral alpha-glucosidase AB (GANAB). Initially distinguished on the basis of differences in electrophoretic mobility in starch gel, GANC and GANAB have been shown to have other differences, including those of substrate specificity. GANC and GANAB are key enzymes in glycogen metabolism that hydrolyze terminal, non-reducing 1,4-linked alpha-D-glucose residues from glycogen in the endoplasmic reticulum. The GANC/GANAB family includes the alpha-glucosidase II (ModA) from Dictyostelium discoideum as well as the alpha-glucosidase II (GLS2, or ROT2 - Reversal of TOR2 lethality protein 2) from Saccharomyces cerevisiae.

glycosyl hydrolase family 31 (GH31). GH31 enzymes occur in prokaryotes, eukaryotes, and archaea with a wide range of hydrolytic activities, including alpha-glucosidase (glucoamylase and sucrase-isomaltase), alpha-xylosidase, 6-alpha-glucosyltransferase, 3-alpha-isomaltosyltransferase and alpha-1,4-glucan lyase. All GH31 enzymes cleave a terminal carbohydrate moiety from a substrate that varies considerably in size, depending on the enzyme, and may be either a starch or a glycoprotein. In most cases, the pyranose moiety recognized in subsite -1 of the substrate binding site is an alpha-D-glucose, though some GH31 family members show a preference for alpha-D-xylose. Several GH31 enzymes can accommodate both glucose and xylose and different levels of discrimination between the two have been observed. Most characterized GH31 enzymes are alpha-glucosidases. In mammals, GH31 members with alpha-glucosidase activity are implicated in at least three distinct biological processes. The lysosomal acid alpha-glucosidase (GAA) is essential for glycogen degradation and a deficiency or malfunction of this enzyme causes glycogen storage disease II, also known as Pompe disease. In the endoplasmic reticulum, alpha-glucosidase II catalyzes the second step in the N-linked oligosaccharide processing pathway that constitutes part of the quality control system for glycoprotein folding and maturation. The intestinal enzymes sucrase-isomaltase (SI) and maltase-glucoamylase (MGAM) play key roles in the final stage of carbohydrate digestion, making alpha-glucosidase inhibitors useful in the treatment of type 2 diabetes. GH31 alpha-glycosidases are retaining enzymes that cleave their substrates via an acid/base-catalyzed, double-displacement mechanism involving a covalent glycosyl-enzyme intermediate. Two aspartic acid residues have been identified as the catalytic nucleophile and the acid/base, respectively.

Alpha-glucosidase II-like. Alpha-glucosidase II (alpha-D-glucoside glucohydrolase) is a glycosyl hydrolase family 31 (GH31) enzyme, found in bacteria and plants, which has exo-alpha-1,4-glucosidase and oligo-1,6-glucosidase activities. Alpha-glucosidase II has been characterized in Bacillus thermoamyloliquefaciens where it forms a homohexamer. This subgroup also includes the MalA alpha-glucosidase from Sulfolobus solfataricus and the AglA alpha-glucosidase from Picrophilus torridus. MalA is part of the carbohydrate-metabolizing machinery that allows this organism to utilize carbohydrates, such as maltose, as the sole carbon and energy source.

Crystalstructure of Paenibacillus sp. 598K alpha-1,6-glucosyltransferase [Paenibacillus sp. 598K],5X7O_B Crystal structure of Paenibacillus sp. 598K alpha-1,6-glucosyltransferase [Paenibacillus sp. 598K],5X7P_A Crystal structure of Paenibacillus sp. 598K alpha-1,6-glucosyltransferase complexed with acarbose [Paenibacillus sp. 598K],5X7P_B Crystal structure of Paenibacillus sp. 598K alpha-1,6-glucosyltransferase complexed with acarbose [Paenibacillus sp. 598K],5X7Q_A Crystal structure of Paenibacillus sp. 598K alpha-1,6-glucosyltransferase complexed with maltohexaose [Paenibacillus sp. 598K],5X7Q_B Crystal structure of Paenibacillus sp. 598K alpha-1,6-glucosyltransferase complexed with maltohexaose [Paenibacillus sp. 598K],5X7R_A Crystal structure of Paenibacillus sp. 598K alpha-1,6-glucosyltransferase complexed with isomaltohexaose [Paenibacillus sp. 598K],5X7R_B Crystal structure of Paenibacillus sp. 598K alpha-1,6-glucosyltransferase complexed with isomaltohexaose [Paenibacillus sp. 598K],5X7S_A Crystal structure of Paenibacillus sp. 598K alpha-1,6-glucosyltransferase, terbium derivative [Paenibacillus sp. 598K],5X7S_B Crystal structure of Paenibacillus sp. 598K alpha-1,6-glucosyltransferase, terbium derivative [Paenibacillus sp. 598K]

Cycloalternan-formingenzyme from Listeria monocytogenes in complex with pentasaccharide substrate [Listeria monocytogenes EGD-e]

Cycloalternan-formingenzyme from Listeria monocytogenes in complex with cycloalternan [Listeria monocytogenes EGD-e],5I0D_B Cycloalternan-forming enzyme from Listeria monocytogenes in complex with cycloalternan [Listeria monocytogenes EGD-e]

1.9Angstrom resolution crystal structure of uncharacterized protein lmo2446 from Listeria monocytogenes EGD-e [Listeria monocytogenes EGD-e],4KWU_A 1.9 Angstrom resolution crystal structure of uncharacterized protein lmo2446 from Listeria monocytogenes EGD-e in complex with alpha-D-glucose, beta-D-glucose, magnesium and calcium [Listeria monocytogenes EGD-e],5HPO_A Cycloalternan-forming enzyme from Listeria monocytogenes in complex with maltopentaose [Listeria monocytogenes EGD-e],5HXM_A Cycloalternan-forming enzyme from Listeria monocytogenes in complex with panose [Listeria monocytogenes]

Flavobacteriumjohnsoniae GH31 dextranase, FjDex31A, mutant D412A complexed with isomaltotriose [Flavobacterium johnsoniae UW101],6JR8_B Flavobacterium johnsoniae GH31 dextranase, FjDex31A, mutant D412A complexed with isomaltotriose [Flavobacterium johnsoniae UW101],6JR8_C Flavobacterium johnsoniae GH31 dextranase, FjDex31A, mutant D412A complexed with isomaltotriose [Flavobacterium johnsoniae UW101],6JR8_D Flavobacterium johnsoniae GH31 dextranase, FjDex31A, mutant D412A complexed with isomaltotriose [Flavobacterium johnsoniae UW101]

Alpha-xylosidase OS=Saccharolobus solfataricus (strain ATCC 35092 / DSM 1617 / JCM 11322 / P2) OX=273057 GN=xylS PE=1 SV=1

Alpha-glucosidase 2 OS=Bacillus thermoamyloliquefaciens OX=1425 PE=3 SV=1

Alpha-xylosidase BoGH31A OS=Bacteroides ovatus (strain ATCC 8483 / DSM 1896 / JCM 5824 / BCRC 10623 / CCUG 4943 / NCTC 11153) OX=411476 GN=BACOVA_02646 PE=1 SV=1

Probable glucan 1,3-alpha-glucosidase OS=Oryza sativa subsp. japonica OX=39947 GN=Os03g0216600 PE=3 SV=1

Probable glucan 1,3-alpha-glucosidase OS=Arabidopsis thaliana OX=3702 GN=PSL5 PE=1 SV=1