Glycosyl hydrolase family 43 proteins similar to Lactobacillus brevis alpha-L-arabinofuranosidase LbAraf43 and Geobacillus thermoleovorans GbtXyl43B. This uncharacterized glycosyl hydrolase family 43 (GH43) subgroup belongs to a subgroup which includes enzymes with beta-xylosidase (EC 3.2.1.37), alpha-L-arabinofuranosidase (EC 3.2.1.55) and possibly bifunctional xylosidase/arabinofuranosidase activities, similar to Lactobacillus brevis alpha-L-arabinofuranosidase LbAraf43 and Geobacillus thermoleovorans IT-08 beta-xylosidase / exo-xylanase (GbtXyl43B). 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 proteins such as Lactobacillus brevis alpha-L-arabinofuranosidase LbAraf43 and Geobacillus thermoleovorans GbtXyl43B. This glycosyl hydrolase family 43 (GH43) subgroup includes enzymes with beta-xylosidase (EC 3.2.1.37), alpha-L-arabinofuranosidase (EC 3.2.1.55) and possibly bifunctional xylosidase/arabinofuranosidase activities. In addition to Lactobacillus brevis alpha-L-arabinofuranosidase LbAraf43 and Geobacillus thermoleovorans IT-08 beta-xylosidase / exo-xylanase (GbtXyl43B). It belongs to the glycosyl hydrolase clan F (according to carbohydrate-active enzymes database (CAZY)) which includes family 43 (GH43) and 62 (GH62) familiesGH43 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 such as Lactobacillus brevis alpha-L-arabinofuranosidase LbAraf43. This glycosyl hydrolase family 43 (GH43) subgroup includes characterized enzymes with alpha-L-arabinofuranosidase (EC 3.2.1.55) activity. 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.

Beta-xylosidase, GH43 family [Carbohydrate transport and metabolism].

Glycosyl hydrolases family 43. The glycosyl hydrolase family 43 contains members that are arabinanases. Arabinanases hydrolyze the alpha-1,5-linked L-arabinofuranoside backbone of plant cell wall arabinans. The structure of arabinanase Arb43A from Cellvibrio japonicus reveals a five-bladed beta-propeller fold. 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 GH43 arabonofuranosidase from Weissella sp. strain 142 [Weissella cibaria],5M8E_B Crystal structure of a GH43 arabonofuranosidase from Weissella sp. strain 142 [Weissella cibaria]

ChainA, Alpha-L-arabinofuranosidase II [Levilactobacillus brevis],5M8B_B Chain B, Alpha-L-arabinofuranosidase II [Levilactobacillus brevis]

Beta-xylosidase,family 43 glycosyl hydrolase from Clostridium acetobutylicum [Clostridium acetobutylicum]