Glycosyl hydrolase family 20 (GH20) catalytic domain of dispersin B (DspB), lacto-N-biosidase (LnbB) and related proteins. Dispersin B is a soluble beta-N-acetylglucosamidase found in bacteria that hydrolyzes the beta-1,6-linkages of PGA (poly-beta-(1,6)-N-acetylglucosamine), a major component of the extracellular polysaccharide matrix. Lacto-N-biosidase hydrolyzes lacto-N-biose (LNB) type I oligosaccharides at the nonreducing terminus to produce lacto-N-biose as part of the GNB/LNB (galacto-N-biose/lacto-N-biose I) degradation pathway. The lacto-N-biosidase from Bifidobacterium bifidum has this GH20 domain, a carbohydrate binding module 32, and a bacterial immunoglobulin-like domain 2, as well as a YSIRK signal peptide and a G5 membrane anchor at the N and C termini, respectively. The GH20 hexosaminidases are thought to act via a catalytic mechanism in which the catalytic nucleophile is not provided by solvent or the enzyme, but by the substrate itself.

Beta-N-acetylhexosaminidases of glycosyl hydrolase family 20 (GH20) catalyze the removal of beta-1,4-linked N-acetyl-D-hexosamine residues from the non-reducing ends of N-acetyl-beta-D-hexosaminides including N-acetylglucosides and N-acetylgalactosides. These enzymes are broadly distributed in microorganisms, plants and animals, and play roles in various key physiological and pathological processes. These processes include cell structural integrity, energy storage, cellular signaling, fertilization, pathogen defense, viral penetration, the development of carcinomas, inflammatory events and lysosomal storage disorders. The GH20 enzymes include the eukaryotic beta-N-acetylhexosaminidases A and B, the bacterial chitobiases, dispersin B, and lacto-N-biosidase. The GH20 hexosaminidases are thought to act via a catalytic mechanism in which the catalytic nucleophile is not provided by the solvent or the enzyme, but by the substrate itself.

Glycosyl hydrolase family 20, catalytic domain. This domain has a TIM barrel fold.

N-acetyl-beta-hexosaminidase [Carbohydrate transport and metabolism].

A subgroup of the Glycosyl hydrolase family 20 (GH20) catalytic domain found in proteins similar to the N-acetylhexosaminidase from Streptomyces plicatus (SpHex). SpHex catalyzes the hydrolysis of N-acetyl-beta-hexosaminides. An Asp residue within the active site plays a critical role in substrate-assisted catalysis by orienting the 2-acetamido group and stabilizing the transition state. The GH20 hexosaminidases are thought to act via a catalytic mechanism in which the catalytic nucleophile is not provided by solvent or the enzyme, but by the substrate itself. Proteins belonging to this subgroup lack the C-terminal PKD (polycystic kidney disease I)-like domain found in the chitobiases.

Crystallizationanalysis of a beta-N-acetylhexosaminidase (Am2136) from Akkermansia muciniphila [Akkermansia muciniphila ATCC BAA-835]

Lacto-N-biosidasefrom Bifidobacterium bifidum [Bifidobacterium bifidum JCM 1254],4H04_B Lacto-N-biosidase from Bifidobacterium bifidum [Bifidobacterium bifidum JCM 1254],4JAW_A Crystal Structure of Lacto-N-Biosidase from Bifidobacterium bifidum complexed with LNB-thiazoline [Bifidobacterium bifidum JCM 1254],4JAW_B Crystal Structure of Lacto-N-Biosidase from Bifidobacterium bifidum complexed with LNB-thiazoline [Bifidobacterium bifidum JCM 1254],5BXP_A LNBase in complex with LNB-LOGNAc [Bifidobacterium bifidum JCM 1254],5BXP_B LNBase in complex with LNB-LOGNAc [Bifidobacterium bifidum JCM 1254],5BXR_A LNBase in complex with LNB-NHAcDNJ [Bifidobacterium bifidum JCM 1254],5BXR_B LNBase in complex with LNB-NHAcDNJ [Bifidobacterium bifidum JCM 1254],5BXS_A LNBase in complex with LNB-NHAcCAS [Bifidobacterium bifidum JCM 1254],5BXS_B LNBase in complex with LNB-NHAcCAS [Bifidobacterium bifidum JCM 1254],5BXT_A LNBase in complex with LNB-NHAcAUS [Bifidobacterium bifidum JCM 1254],5BXT_B LNBase in complex with LNB-NHAcAUS [Bifidobacterium bifidum JCM 1254]

Crystalstructure of beta-hexosaminidase from Paenibacillus sp. TS12 [Paenibacillus sp.],3GH5_A Crystal structure of beta-hexosaminidase from Paenibacillus sp. TS12 in complex with GlcNAc [Paenibacillus sp.],3GH7_A Crystal structure of beta-hexosaminidase from Paenibacillus sp. TS12 in complex with GalNAc [Paenibacillus sp.],3SUR_A Crystal structure of beta-hexosaminidase from Paenibacillus sp. TS12 in complex with NAG-thiazoline. [Paenibacillus sp. TS12],3SUS_A Crystal structure of beta-hexosaminidase from Paenibacillus sp. TS12 in complex with Gal-NAG-thiazoline [Paenibacillus sp. TS12],3SUT_A Crystal structure of beta-hexosaminidase from Paenibacillus sp. TS12 in complex with PUGNAc [Paenibacillus sp. TS12],3SUU_A Crystal structure of beta-hexosaminidase from Paenibacillus sp. TS12 in complex with Gal-PUGNAc [Paenibacillus sp. TS12],3SUV_A Crystal structure of beta-hexosaminidase from Paenibacillus sp. TS12 in complex with NHAc-DNJ [Paenibacillus sp. TS12],3SUW_A Crystal structure of beta-hexosaminidase from Paenibacillus sp. TS12 in complex with NHAc-CAS [Paenibacillus sp. TS12]

ChainA, Beta-N-acetylhexosaminidase [Bacteroides thetaiotaomicron],7DVA_A Chain A, Beta-N-acetylhexosaminidase [Bacteroides thetaiotaomicron],7DVA_B Chain B, Beta-N-acetylhexosaminidase [Bacteroides thetaiotaomicron]

ChainA, Beta-N-acetylhexosaminidase [Bacteroides thetaiotaomicron],7DVB_B Chain B, Beta-N-acetylhexosaminidase [Bacteroides thetaiotaomicron],7DVB_C Chain C, Beta-N-acetylhexosaminidase [Bacteroides thetaiotaomicron],7DVB_D Chain D, Beta-N-acetylhexosaminidase [Bacteroides thetaiotaomicron]

Beta-hexosaminidase Amuc_2136 OS=Akkermansia muciniphila (strain ATCC BAA-835 / DSM 22959 / JCM 33894 / BCRC 81048 / CCUG 64013 / CIP 107961 / Muc) OX=349741 GN=Amuc_2136 PE=1 SV=1

Beta-hexosaminidase OS=Vibrio furnissii OX=29494 GN=exoI PE=1 SV=1

Beta-N-acetylhexosaminidase OS=Cellulomonas fimi OX=1708 GN=hex20 PE=1 SV=1

Beta-hexosaminidase Amuc_2018 OS=Akkermansia muciniphila (strain ATCC BAA-835 / DSM 22959 / JCM 33894 / BCRC 81048 / CCUG 64013 / CIP 107961 / Muc) OX=349741 GN=Amuc_2018 PE=1 SV=1

N,N'-diacetylchitobiase OS=Vibrio harveyi OX=669 GN=chb PE=1 SV=1