Glycosyl hydrolase family 43 protein such as Aspergillus niger DMS1957 xylanase D (XlnD); includes mostly xylanases. This glycosyl hydrolase family 43 (GH43) subgroup includes enzymes that have mostly been annotated as xylanases (endo-alpha-L-arabinanase, EC 3.2.1.8). It belongs to the GH43_bXyl-like subgroup of the glycosyl hydrolase clan F (according to carbohydrate-active enzymes database (CAZY)) which includes family 43 (GH43) and 62 (GH62) families. The GH43_bXyl-like subgroup includes enzymes that have been annotated as xylan-digesting beta-xylosidases (EC 3.2.1.37) and xylanases, as well the Bacteroides thetaiotaomicron VPI-5482 alpha-L-arabinofuranosidases (EC 3.2.1.55) (BT3675;BT_3675) and (BT3662;BT_3662). GH43 are inverting enzymes (i.e. they invert the stereochemistry of the anomeric carbon atom of the substrate) that have an aspartate as the catalytic general base, a glutamate as the catalytic general acid and another aspartate that is responsible for pKa modulation and orienting the catalytic acid. Many GH43 enzymes display both alpha-L-arabinofuranosidase and beta-D-xylosidase activity using aryl-glycosides as substrates. A common structural feature of GH43 enzymes is a 5-bladed beta-propeller domain that contains the catalytic acid and catalytic base. A long V-shaped groove, partially enclosed at one end, forms a single extended substrate-binding surface across the face of the propeller.

Glycosyl hydrolase family 43 protein such as Bacteroides thetaiotaomicron VPI-5482 alpha-L-arabinofuranosidases (BT3675;BT_3675) and (BT3662;BT_3662); includes mostly xylanases. This glycosyl hydrolase family 43 (GH43) subgroup includes enzymes that have been annotated as xylan-digesting beta-xylosidase (EC 3.2.1.37) and xylanase (endo-alpha-L-arabinanase, EC 3.2.1.8) activities, as well the Bacteroides thetaiotaomicron VPI-5482 alpha-L-arabinofuranosidases (EC 3.2.1.55) (BT3675;BT_3675) and (BT3662;BT_3662). It belongs to the glycosyl hydrolase clan F (according to carbohydrate-active enzymes database (CAZY)) which includes family 43 (GH43) and 62 (GH62) families. GH43 are inverting enzymes (i.e. they invert the stereochemistry of the anomeric carbon atom of the substrate) that have an aspartate as the catalytic general base, a glutamate as the catalytic general acid and another aspartate that is responsible for pKa modulation and orienting the catalytic acid. Many GH43 enzymes display both alpha-L-arabinofuranosidase and beta-D-xylosidase activity using aryl-glycosides as substrates. A common structural feature of GH43 enzymes is a 5-bladed beta-propeller domain that contains the catalytic acid and catalytic base. A long V-shaped groove, partially enclosed at one end, forms a single extended substrate-binding surface across the face of the propeller.

Glycosyl hydrolase family 43 protein most having a F5/8 type C domain C-terminal to the GH43 domain. This glycosyl hydrolase family 43 (GH43) subgroup includes enzymes that have been annotated as having beta-xylosidase (EC 3.2.1.37), xylanase (EC 3.2.1.8), and beta-galactosidase (EC 3.2.1.145) activities, and some as F5/8 type C domain (also known as the discoidin (DS) domain)-containing proteins. Most contain a F5/8 type C domain C-terminal to the GH43 domain. It belongs to the glycosyl hydrolase clan F (according to carbohydrate-active enzymes database (CAZY)) which includes family 43 (GH43) and 62 (GH62) families. GH43 are inverting enzymes (i.e. they invert the stereochemistry of the anomeric carbon atom of the substrate) that have an aspartate as the catalytic general base, a glutamate as the catalytic general acid and another aspartate that is responsible for pKa modulation and orienting the catalytic acid. Many GH43 enzymes display both alpha-L-arabinofuranosidase and beta-D-xylosidase activity using aryl-glycosides as substrates. Characterized enzymes belonging to this subgroup include Lactobacillus brevis (LbAraf43) and Weissella sp (WAraf43) which show activity with similar catalytic efficiency on 1,5-alpha-L-arabinooligosaccharides with a degree of polymerization (DP) of 2-3; size is limited by an extended loop at the entrance to the active site. A common structural feature of GH43 enzymes is a 5-bladed beta-propeller domain that contains the catalytic acid and catalytic base. A long V-shaped groove, partially enclosed at one end, forms a single extended substrate-binding surface across the face of the propeller.

Glycosyl hydrolase family 43 protein such as Halothermothrix orenii H 168 alpha-L-arabinofuranosidase (HoAraf43;Hore_20580). This glycosyl hydrolase family 43 (GH43) subgroup includes Halothermothrix orenii H 168 alpha-L-arabinofuranosidase (EC 3.2.1.55) (HoAraf43;Hore_20580). It belongs to the glycosyl hydrolase clan F (according to carbohydrate-active enzymes database (CAZY)) which includes family 43 (GH43) and 62 (GH62) families. This GH43_ HoAraf43-like subgroup includes enzymes that have been annotated as having xylan-digesting beta-xylosidase (EC 3.2.1.37) and xylanase (endo-alpha-L-arabinanase, EC 3.2.1.8) activities. GH43 are inverting enzymes (i.e. they invert the stereochemistry of the anomeric carbon atom of the substrate) that have an aspartate as the catalytic general base, a glutamate as the catalytic general acid and another aspartate that is responsible for pKa modulation and orienting the catalytic acid. Many GH43 enzymes display both alpha-L-arabinofuranosidase and beta-D-xylosidase activity using aryl-glycosides as substrates. A common structural feature of GH43 enzymes is a 5-bladed beta-propeller domain that contains the catalytic acid and catalytic base. A long V-shaped groove, partially enclosed at one end, forms a single extended substrate-binding surface across the face of the propeller.

Glycosyl hydrolase family 43 protein, includes arabinoxylan arabinofuranohydrolase, beta-xylosidase, endo-1,4-beta-xylanase, and alpha-L-arabinofuranosidase. This subgroup includes Bacillus subtilis arabinoxylan arabinofuranohydrolase (XynD;BsAXH-m23;BSU18160), Butyrivibrio proteoclasticus alpha-L-arabinofuranosidase (Xsa43E;bpr_I2319), Clostridium stercorarium alpha-L-arabinofuranosidase XylA, and metagenomic beta-xylosidase (EC 3.2.1.37) / alpha-L-arabinofuranosidase (EC 3.2.1.55) CoXyl43. It belongs to the glycosyl hydrolase clan F (according to carbohydrate-active enzymes database (CAZY)) which includes family 43 (GH43) and 62 (GH62) families. The GH43_AXH-like subgroup includes enzymes that have been characterized with beta-xylosidase, alpha-L-arabinofuranosidase, endo-alpha-L-arabinanase as well as arabinoxylan arabinofuranohydrolase (AXH) activities. GH43 are inverting enzymes (i.e. they invert the stereochemistry of the anomeric carbon atom of the substrate) that have an aspartate as the catalytic general base, a glutamate as the catalytic general acid and another aspartate that is responsible for pKa modulation and orienting the catalytic acid. Many GH43 enzymes display both alpha-L-arabinofuranosidase and beta-D-xylosidase activity using aryl-glycosides as substrates. AXHs specifically hydrolyze the glycosidic bond between arabinofuranosyl substituents and xylopyranosyl backbone residues of arabinoxylan. Metagenomic beta-xylosidase/alpha-L-arabinofuranosidase CoXyl43 shows synergy with Trichoderma reesei cellulases and promotes plant biomass saccharification by degrading xylo-oligosaccharides, such as xylobiose and xylotriose, into the monosaccharide xylose. Studies show that the hydrolytic activity of CoXyl43 is stimulated in the presence of calcium. Several of these enzymes also contain carbohydrate binding modules (CBMs) that bind cellulose or xylan. A common structural feature of GH43 enzymes is a 5-bladed beta-propeller domain that contains the catalytic acid and catalytic base. A long V-shaped groove, partially enclosed at one end, forms a single extended substrate-binding surface across the face of the propeller.

Crystalstructure of a thermostable family-43 glycoside hydrolase [Halothermothrix orenii H 168],4QQS_B Crystal structure of a thermostable family-43 glycoside hydrolase [Halothermothrix orenii H 168]

ChainA, CARBOHYDRATE BINDING FAMILY 6 [Acetivibrio thermocellus],5A8D_A Chain A, CARBOHYDRATE BINDING FAMILY 6 [Acetivibrio thermocellus]

Xsa43E,a GH43 family enzyme from Butyrivibrio proteoclasticus [Butyrivibrio proteoclasticus B316]

Crystalstructure of Endo-1,4-beta-xylanase (NP_811807.1) from BACTEROIDES THETAIOTAOMICRON VPI-5482 at 1.70 A resolution [Bacteroides thetaiotaomicron VPI-5482],3KST_B Crystal structure of Endo-1,4-beta-xylanase (NP_811807.1) from BACTEROIDES THETAIOTAOMICRON VPI-5482 at 1.70 A resolution [Bacteroides thetaiotaomicron VPI-5482]

Crystalstructure of CoXyl43, GH43 beta-xylosidase/alpha-arabinofuranosidase from a compost microbial metagenome, calcium-free form. [uncultured bacterium],5GLK_B Crystal structure of CoXyl43, GH43 beta-xylosidase/alpha-arabinofuranosidase from a compost microbial metagenome, calcium-free form. [uncultured bacterium],5GLL_A Crystal structure of CoXyl43, GH43 beta-xylosidase/alpha-arabinofuranosidase from a compostmicrobial metagenome, calcium-bound form [uncultured bacterium],5GLL_B Crystal structure of CoXyl43, GH43 beta-xylosidase/alpha-arabinofuranosidase from a compostmicrobial metagenome, calcium-bound form [uncultured bacterium],5GLM_A Crystal structure of CoXyl43, GH43 beta-xylosidase/alpha-arabinofuranosidase from a compost microbial metagenome in complex with xylotriose, calcium-free form. [uncultured bacterium],5GLM_B Crystal structure of CoXyl43, GH43 beta-xylosidase/alpha-arabinofuranosidase from a compost microbial metagenome in complex with xylotriose, calcium-free form. [uncultured bacterium],5GLN_A Crystal structure of CoXyl43, GH43 beta-xylosidase/alpha-arabinofuranosidase from a compostmicrobial metagenome in complex with xylotriose, calcium-bound form [uncultured bacterium],5GLN_B Crystal structure of CoXyl43, GH43 beta-xylosidase/alpha-arabinofuranosidase from a compostmicrobial metagenome in complex with xylotriose, calcium-bound form [uncultured bacterium],5GLO_A Crystal structure of CoXyl43, GH43 beta-xylosidase/alpha-arabinofuranosidase from a compostmicrobial metagenome in complex with l-arabinose, calcium-free form [uncultured bacterium],5GLO_B Crystal structure of CoXyl43, GH43 beta-xylosidase/alpha-arabinofuranosidase from a compostmicrobial metagenome in complex with l-arabinose, calcium-free form [uncultured bacterium],5GLP_A Crystal structure of CoXyl43, GH43 beta-xylosidase/alpha-arabinofuranosidase from a compostmicrobial metagenome in complex with l-arabinose, calcium-bound form [uncultured bacterium],5GLP_B Crystal structure of CoXyl43, GH43 beta-xylosidase/alpha-arabinofuranosidase from a compostmicrobial metagenome in complex with l-arabinose, calcium-bound form [uncultured bacterium],5GLQ_A Crystal structure of CoXyl43, GH43 beta-xylosidase/alpha-arabinofuranosidase from a compostmicrobial metagenome in complex with l-arabinose and xylotriose, calcium-free form [uncultured bacterium],5GLQ_B Crystal structure of CoXyl43, GH43 beta-xylosidase/alpha-arabinofuranosidase from a compostmicrobial metagenome in complex with l-arabinose and xylotriose, calcium-free form [uncultured bacterium],5GLR_A Crystal structure of CoXyl43, GH43 beta-xylosidase/alpha-arabinofuranosidase from a compostmicrobial metagenome in complex with l-arabinose and xylotriose, calcium-bound form [uncultured bacterium],5GLR_B Crystal structure of CoXyl43, GH43 beta-xylosidase/alpha-arabinofuranosidase from a compostmicrobial metagenome in complex with l-arabinose and xylotriose, calcium-bound form [uncultured bacterium]

Beta-xylosidase OS=Prevotella ruminicola OX=839 GN=xynB PE=3 SV=1

Xylosidase/arabinosidase OS=Bacteroides ovatus OX=28116 GN=xsa PE=2 SV=1

Arabinoxylan arabinofuranohydrolase OS=Bacillus subtilis (strain 168) OX=224308 GN=xynD PE=1 SV=2

Arabinoxylan arabinofuranohydrolase OS=Paenibacillus polymyxa OX=1406 GN=xynD PE=1 SV=1

Xylosidase/arabinosidase OS=Butyrivibrio fibrisolvens OX=831 GN=xylB PE=3 SV=1