xylosidase XylS-like. XylS is a glycosyl hydrolase family 31 (GH31) alpha-xylosidase found in prokaryotes, eukaryotes, and archaea, that catalyzes the release of alpha-xylose from the non-reducing terminal side of the alpha-xyloside substrate. XylS has been characterized in Sulfolobus solfataricus where it hydrolyzes isoprimeverose, the p-nitrophenyl-beta derivative of isoprimeverose, and xyloglucan oligosaccharides, and has transxylosidic activity. 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 XylS family corresponds to subgroup 3 in the Ernst et al classification of GH31 enzymes.

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.

N-terminal domain of glycosyl hydrolase family 31 (GH31). This family is found N-terminal to the glycosyl-hydrolase domain of Glycoside hydrolase family 31 (GH31). GH31 includes the glycoside hydrolases alpha-glucosidase (EC 3.2.1.20), alpha-1,3-glucosidase (EC 3.2.1.84), alpha-xylosidase (EC 3.2.1.177), sucrase-isomaltase (EC 3.2.1.48 and EC 3.2.1.10), as well as alpha-glucan lyase (EC 4.2.2.13). 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 of the catalytic domain have been identified as the catalytic nucleophile and the acid/base, respectively. A loop of the N-terminal beta-sandwich domain is part of the active site pocket.

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.

crystalstructure of alpha-xylosidase (GH31) from Cellvibrio japonicus [Cellvibrio japonicus],2XVK_A crystal structure of alpha-xylosidase (GH31) from Cellvibrio japonicus in complex with 5-fluoro-alpha-D-xylopyranosyl fluoride [Cellvibrio japonicus],2XVL_A crystal structure of alpha-xylosidase (GH31) from Cellvibrio japonicus in complex with Pentaerythritol propoxylate (5 4 PO OH) [Cellvibrio japonicus]

ChainA, Alpha-xylosidase [Xanthomonas citri pv. citri str. 306],7KNC_A Chain A, Alpha-xylosidase [Xanthomonas citri pv. citri str. 306]

Bacteroidesovatus Xyloglucan PUL GH31 [Bacteroides ovatus],5JOV_A Bacteroides ovatus Xyloglucan PUL GH31 with bound 5FIdoF [Bacteroides ovatus]

Xylosidasefrom Aspergillus niger [Aspergillus niger],6DRU_B Xylosidase from Aspergillus niger [Aspergillus niger]

CrystalStructure of Apo Agd31B, alpha-transglucosylase in Glycoside Hydrolase Family 31 [Cellvibrio japonicus],4B9Z_A Crystal Structure of Agd31B, alpha-transglucosylase, complexed with Acarbose [Cellvibrio japonicus],4BA0_A Crystal Structure of Agd31B, alpha-transglucosylase, complexed with 5F-alpha-GlcF [Cellvibrio japonicus]

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

Uncharacterized family 31 glucosidase ORF2 (Fragment) OS=Pseudescherichia vulneris OX=566 PE=3 SV=1

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

Alpha-xylosidase A OS=Aspergillus niger (strain CBS 513.88 / FGSC A1513) OX=425011 GN=axlA PE=1 SV=1