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

CtsY (cyclic tetrasaccharide-synthesizing enzyme Y)-like. CtsY is a bacterial 3-alpha-isomaltosyltransferase, first identified in Arthrobacter globiformis, that produces cyclic tetrasaccharides together with a closely related enzyme CtsZ. CtsY and CtsZ both have a glycosyl hydrolase family 31 (GH31) catalytic domain; CtsZ belongs to a different subfamily. 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.

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

putative alpha-glucosidase; Provisional

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.

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]

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]

Cycloalternan-degradingenzyme from Trueperella pyogenes [Trueperella pyogenes],5F7S_B Cycloalternan-degrading enzyme from Trueperella pyogenes [Trueperella pyogenes],5I0E_B Cycloalternan-degrading enzyme from Trueperella pyogenes in complex with isomaltose [Trueperella pyogenes],5I0F_B Cycloalternan-degrading enzyme from Trueperella pyogenes in complex with covalent intermediate [Trueperella pyogenes]

Cycloalternan-degradingenzyme from Trueperella pyogenes in complex with cycloalternan [Trueperella pyogenes]

1,3-alpha-isomaltosidase OS=Kribbella flavida (strain DSM 17836 / JCM 10339 / NBRC 14399) OX=479435 GN=Kfla_1895 PE=1 SV=1

Alpha-xylosidase OS=Escherichia coli (strain K12) OX=83333 GN=yicI PE=1 SV=2

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

Alpha-xylosidase XylQ OS=Lactiplantibacillus pentosus OX=1589 GN=xylQ PE=1 SV=1

Alpha-xylosidase OS=Emericella nidulans (strain FGSC A4 / ATCC 38163 / CBS 112.46 / NRRL 194 / M139) OX=227321 GN=agdD PE=1 SV=1