putative alpha-glucosidase; Provisional

alpha-xylosidase YicI-like. YicI alpha-xylosidase is a glycosyl hydrolase family 31 (GH31) enzyme that catalyzes the release of an alpha-xylosyl residue from the non-reducing end of alpha-xyloside substrates such as alpha-xylosyl fluoride and isoprimeverose. YicI forms a homohexamer (a trimer of dimers). 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. The YicI family corresponds to subgroup 4 in the Ernst et al classification of GH31 enzymes.

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

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

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.

Structureof a Family 31 alpha glycosidase [Escherichia coli],1XSI_B Structure of a Family 31 alpha glycosidase [Escherichia coli],1XSI_C Structure of a Family 31 alpha glycosidase [Escherichia coli],1XSI_D Structure of a Family 31 alpha glycosidase [Escherichia coli],1XSI_E Structure of a Family 31 alpha glycosidase [Escherichia coli],1XSI_F Structure of a Family 31 alpha glycosidase [Escherichia coli],1XSJ_A Structure of a Family 31 alpha glycosidase [Escherichia coli],1XSJ_B Structure of a Family 31 alpha glycosidase [Escherichia coli],1XSJ_C Structure of a Family 31 alpha glycosidase [Escherichia coli],1XSJ_D Structure of a Family 31 alpha glycosidase [Escherichia coli],1XSJ_E Structure of a Family 31 alpha glycosidase [Escherichia coli],1XSJ_F Structure of a Family 31 alpha glycosidase [Escherichia coli],1XSK_A Structure of a Family 31 alpha glycosidase glycosyl-enzyme intermediate [Escherichia coli],1XSK_B Structure of a Family 31 alpha glycosidase glycosyl-enzyme intermediate [Escherichia coli],1XSK_C Structure of a Family 31 alpha glycosidase glycosyl-enzyme intermediate [Escherichia coli],1XSK_D Structure of a Family 31 alpha glycosidase glycosyl-enzyme intermediate [Escherichia coli],1XSK_E Structure of a Family 31 alpha glycosidase glycosyl-enzyme intermediate [Escherichia coli],1XSK_F Structure of a Family 31 alpha glycosidase glycosyl-enzyme intermediate [Escherichia coli]

Structureof the YicI thiosugar Michaelis complex [Escherichia coli],2F2H_B Structure of the YicI thiosugar Michaelis complex [Escherichia coli],2F2H_C Structure of the YicI thiosugar Michaelis complex [Escherichia coli],2F2H_D Structure of the YicI thiosugar Michaelis complex [Escherichia coli],2F2H_E Structure of the YicI thiosugar Michaelis complex [Escherichia coli],2F2H_F Structure of the YicI thiosugar Michaelis complex [Escherichia coli]

CrystalStructure of Alpha-Xylosidase from Escherichia coli [Escherichia coli],1WE5_B Crystal Structure of Alpha-Xylosidase from Escherichia coli [Escherichia coli],1WE5_C Crystal Structure of Alpha-Xylosidase from Escherichia coli [Escherichia coli],1WE5_D Crystal Structure of Alpha-Xylosidase from Escherichia coli [Escherichia coli],1WE5_E Crystal Structure of Alpha-Xylosidase from Escherichia coli [Escherichia coli],1WE5_F Crystal Structure of Alpha-Xylosidase from Escherichia coli [Escherichia coli]

Crystalstructure of Family 31 alpha-glucosidase (BT_0339) from Bacteroides thetaiotaomicron [Bacteroides thetaiotaomicron VPI-5482],5F7C_B Crystal structure of Family 31 alpha-glucosidase (BT_0339) from Bacteroides thetaiotaomicron [Bacteroides thetaiotaomicron VPI-5482],5F7C_C Crystal structure of Family 31 alpha-glucosidase (BT_0339) from Bacteroides thetaiotaomicron [Bacteroides thetaiotaomicron VPI-5482],5F7C_D Crystal structure of Family 31 alpha-glucosidase (BT_0339) from Bacteroides thetaiotaomicron [Bacteroides thetaiotaomicron VPI-5482]

Flavobacteriumjohnsoniae GH31 dextranase, FjDex31A [Flavobacterium johnsoniae UW101],6JR6_B Flavobacterium johnsoniae GH31 dextranase, FjDex31A [Flavobacterium johnsoniae UW101],6JR6_C Flavobacterium johnsoniae GH31 dextranase, FjDex31A [Flavobacterium johnsoniae UW101],6JR6_D Flavobacterium johnsoniae GH31 dextranase, FjDex31A [Flavobacterium johnsoniae UW101],6JR7_A Flavobacterium johnsoniae GH31 dextranase, FjDex31A, complexed with glucose [Flavobacterium johnsoniae UW101],6JR7_B Flavobacterium johnsoniae GH31 dextranase, FjDex31A, complexed with glucose [Flavobacterium johnsoniae UW101],6JR7_C Flavobacterium johnsoniae GH31 dextranase, FjDex31A, complexed with glucose [Flavobacterium johnsoniae UW101],6JR7_D Flavobacterium johnsoniae GH31 dextranase, FjDex31A, complexed with glucose [Flavobacterium johnsoniae UW101]

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

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

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

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

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