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Conserved domains on  [gi|755538560|ref|XP_011247304|]
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hexosaminidase D isoform X3 [Mus musculus]

Protein Classification

beta-N-acetylhexosaminidase( domain architecture ID 10159022)

beta-N-acetylhexosaminidase catalyzes the hydrolysis of terminal non-reducing N-acetyl-D-hexosamine residues in N-acetyl-beta-D-hexosaminides

Graphical summary

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List of domain hits

Name Accession Description Interval E-value
GH20_GcnA-like cd06565
Glycosyl hydrolase family 20 (GH20) catalytic domain of N-acetyl-beta-D-glucosaminidase (GcnA, ...
9-323 4.00e-128

Glycosyl hydrolase family 20 (GH20) catalytic domain of N-acetyl-beta-D-glucosaminidase (GcnA, also known as BhsA) and related proteins. GcnA is an exoglucosidase which cleaves N-acetyl-beta-D-galactosamine (NAG) and N-acetyl-beta-D-galactosamine residues from 4-methylumbelliferylated (4MU) substrates, as well as cleaving NAG from chito-oligosaccharides (i.e. NAG polymers). In contrast, sulfated forms of the substrate are unable to be cleaved and act instead as mild competitive inhibitors. Additionally, the enzyme is known to be poisoned by several first-row transition metals as well as by mercury. GcnA forms a homodimer with subunits comprised of three domains, an N-terminal zincin-like domain, this central catalytic GH20 domain, and a C-terminal alpha helical domain. 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.


:

Pssm-ID: 119335  Cd Length: 301  Bit Score: 372.69  E-value: 4.00e-128
                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 755538560   9 MRLVHLDLKG-APPKVSYLSEVFPLFHALGANGLLIEYEDMFPYEGHLRLLRAKHAYSPSEVTEILRLARLSELEVIPLV 87
Cdd:cd06565    1 FRGVHLDLKRnAVPKVSYLKKLLRLLALLGANGLLLYYEDTFPYEGEPEVGRMRGAYTKEEIREIDDYAAELGIEVIPLI 80
                         90       100       110       120       130       140       150       160
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 755538560  88 QTFGHMEFVLKHAAFAHLREVALFPNTLNPHEAESLALVQAMIDQILELHRdVRWLHIGCDEVYYLGEGETSKQWlqqEQ 167
Cdd:cd06565   81 QTLGHLEFILKHPEFRHLREVDDPPQTLCPGEPKTYDFIEEMIRQVLELHP-SKYIHIGMDEAYDLGRGRSLRKH---GN 156
                        170       180       190       200       210       220       230       240
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 755538560 168 NSHAKLCLSHMQAVASHVLTQHPgvTPLVWDDMLRDIPQEQLKASGVPQLVEPVLWDYGADLDVHGKVFLIGKYQECGFQ 247
Cdd:cd06565  157 LGRGELYLEHLKKVLKIIKKRGP--KPMMWDDMLRKLSIEPEALSGLPKLVTPVVWDYYADLDEHDRPIGLWKKYGSVFA 234
                        250       260       270       280       290       300       310
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*.
gi 755538560 248 RLWAASAFKGATgasqalPPVEHHIRNHELWLQVAgsgPKDALQGIILTGWQRYDHFSVLCELLPVGIPSLAACLQ 323
Cdd:cd06565  235 VAWGASAWKGAT------PPNDKHLENIKSWLKAA---KKNGVQGILLTGWGDYGHEAVLCELLPGLIPSLALALG 301
 
Name Accession Description Interval E-value
GH20_GcnA-like cd06565
Glycosyl hydrolase family 20 (GH20) catalytic domain of N-acetyl-beta-D-glucosaminidase (GcnA, ...
9-323 4.00e-128

Glycosyl hydrolase family 20 (GH20) catalytic domain of N-acetyl-beta-D-glucosaminidase (GcnA, also known as BhsA) and related proteins. GcnA is an exoglucosidase which cleaves N-acetyl-beta-D-galactosamine (NAG) and N-acetyl-beta-D-galactosamine residues from 4-methylumbelliferylated (4MU) substrates, as well as cleaving NAG from chito-oligosaccharides (i.e. NAG polymers). In contrast, sulfated forms of the substrate are unable to be cleaved and act instead as mild competitive inhibitors. Additionally, the enzyme is known to be poisoned by several first-row transition metals as well as by mercury. GcnA forms a homodimer with subunits comprised of three domains, an N-terminal zincin-like domain, this central catalytic GH20 domain, and a C-terminal alpha helical domain. 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.


Pssm-ID: 119335  Cd Length: 301  Bit Score: 372.69  E-value: 4.00e-128
                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 755538560   9 MRLVHLDLKG-APPKVSYLSEVFPLFHALGANGLLIEYEDMFPYEGHLRLLRAKHAYSPSEVTEILRLARLSELEVIPLV 87
Cdd:cd06565    1 FRGVHLDLKRnAVPKVSYLKKLLRLLALLGANGLLLYYEDTFPYEGEPEVGRMRGAYTKEEIREIDDYAAELGIEVIPLI 80
                         90       100       110       120       130       140       150       160
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 755538560  88 QTFGHMEFVLKHAAFAHLREVALFPNTLNPHEAESLALVQAMIDQILELHRdVRWLHIGCDEVYYLGEGETSKQWlqqEQ 167
Cdd:cd06565   81 QTLGHLEFILKHPEFRHLREVDDPPQTLCPGEPKTYDFIEEMIRQVLELHP-SKYIHIGMDEAYDLGRGRSLRKH---GN 156
                        170       180       190       200       210       220       230       240
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 755538560 168 NSHAKLCLSHMQAVASHVLTQHPgvTPLVWDDMLRDIPQEQLKASGVPQLVEPVLWDYGADLDVHGKVFLIGKYQECGFQ 247
Cdd:cd06565  157 LGRGELYLEHLKKVLKIIKKRGP--KPMMWDDMLRKLSIEPEALSGLPKLVTPVVWDYYADLDEHDRPIGLWKKYGSVFA 234
                        250       260       270       280       290       300       310
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*.
gi 755538560 248 RLWAASAFKGATgasqalPPVEHHIRNHELWLQVAgsgPKDALQGIILTGWQRYDHFSVLCELLPVGIPSLAACLQ 323
Cdd:cd06565  235 VAWGASAWKGAT------PPNDKHLENIKSWLKAA---KKNGVQGILLTGWGDYGHEAVLCELLPGLIPSLALALG 301
Glyco_hydro_20 pfam00728
Glycosyl hydrolase family 20, catalytic domain; This domain has a TIM barrel fold.
64-203 4.79e-08

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


Pssm-ID: 425840  Cd Length: 344  Bit Score: 54.61  E-value: 4.79e-08
                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 755538560   64 YSPSEVTEILRLARLSELEVIPLVQTFGHM--------EFVLKHAAFAHLREVAL--FPNTLNPHEAESLALVQAMIDQI 133
Cdd:pfam00728  75 YTQEDIREIVAYAAARGIRVIPEIDMPGHAraalaaypELGCGCGADSPWVSVQWgpPEGQLNPGNEKTYTFLDNVFDEV 154
                          90       100       110       120       130       140       150
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*...
gi 755538560  134 LELHRDvRWLHIGCDEVyylgegeTSKQWLQQE--QNSHAKLCLSHMQAVAS------HVLTQHPGVTPLVWDDMLRD 203
Cdd:pfam00728 155 ADLFPS-DYIHIGGDEV-------PKGCWEKSPecQARMKEEGLKSLHELQQyfikraSKIVSSKGRRLIGWDEILDG 224
 
Name Accession Description Interval E-value
GH20_GcnA-like cd06565
Glycosyl hydrolase family 20 (GH20) catalytic domain of N-acetyl-beta-D-glucosaminidase (GcnA, ...
9-323 4.00e-128

Glycosyl hydrolase family 20 (GH20) catalytic domain of N-acetyl-beta-D-glucosaminidase (GcnA, also known as BhsA) and related proteins. GcnA is an exoglucosidase which cleaves N-acetyl-beta-D-galactosamine (NAG) and N-acetyl-beta-D-galactosamine residues from 4-methylumbelliferylated (4MU) substrates, as well as cleaving NAG from chito-oligosaccharides (i.e. NAG polymers). In contrast, sulfated forms of the substrate are unable to be cleaved and act instead as mild competitive inhibitors. Additionally, the enzyme is known to be poisoned by several first-row transition metals as well as by mercury. GcnA forms a homodimer with subunits comprised of three domains, an N-terminal zincin-like domain, this central catalytic GH20 domain, and a C-terminal alpha helical domain. 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.


Pssm-ID: 119335  Cd Length: 301  Bit Score: 372.69  E-value: 4.00e-128
                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 755538560   9 MRLVHLDLKG-APPKVSYLSEVFPLFHALGANGLLIEYEDMFPYEGHLRLLRAKHAYSPSEVTEILRLARLSELEVIPLV 87
Cdd:cd06565    1 FRGVHLDLKRnAVPKVSYLKKLLRLLALLGANGLLLYYEDTFPYEGEPEVGRMRGAYTKEEIREIDDYAAELGIEVIPLI 80
                         90       100       110       120       130       140       150       160
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 755538560  88 QTFGHMEFVLKHAAFAHLREVALFPNTLNPHEAESLALVQAMIDQILELHRdVRWLHIGCDEVYYLGEGETSKQWlqqEQ 167
Cdd:cd06565   81 QTLGHLEFILKHPEFRHLREVDDPPQTLCPGEPKTYDFIEEMIRQVLELHP-SKYIHIGMDEAYDLGRGRSLRKH---GN 156
                        170       180       190       200       210       220       230       240
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 755538560 168 NSHAKLCLSHMQAVASHVLTQHPgvTPLVWDDMLRDIPQEQLKASGVPQLVEPVLWDYGADLDVHGKVFLIGKYQECGFQ 247
Cdd:cd06565  157 LGRGELYLEHLKKVLKIIKKRGP--KPMMWDDMLRKLSIEPEALSGLPKLVTPVVWDYYADLDEHDRPIGLWKKYGSVFA 234
                        250       260       270       280       290       300       310
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*.
gi 755538560 248 RLWAASAFKGATgasqalPPVEHHIRNHELWLQVAgsgPKDALQGIILTGWQRYDHFSVLCELLPVGIPSLAACLQ 323
Cdd:cd06565  235 VAWGASAWKGAT------PPNDKHLENIKSWLKAA---KKNGVQGILLTGWGDYGHEAVLCELLPGLIPSLALALG 301
GH20_hexosaminidase cd02742
Beta-N-acetylhexosaminidases of glycosyl hydrolase family 20 (GH20) catalyze the removal of ...
60-298 1.48e-12

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.


Pssm-ID: 119331 [Multi-domain]  Cd Length: 303  Bit Score: 68.23  E-value: 1.48e-12
                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 755538560  60 AKHAYSPSEVTEILRLARLSELEVIPLVQTFGHMEFVLKhaAFAHLR-EVALFPNT------LNPHEAESLALVQAMIDQ 132
Cdd:cd02742   65 PGGFYTYAQLKDIIEYAAARGIEVIPEIDMPGHSTAFVK--SFPKLLtECYAGLKLrdvfdpLDPTLPKGYDFLDDLFGE 142
                         90       100       110       120       130       140       150       160
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 755538560 133 ILELHrDVRWLHIGCDEVYYlgegetskqwlqqEQNSHAKLClSHMQAVASHVLTQhpGVTPLVWDDMLrdIPQEQLKAS 212
Cdd:cd02742  143 IAELF-PDRYLHIGGDEAHF-------------KQDRKHLMS-QFIQRVLDIVKKK--GKKVIVWQDGF--DKKMKLKED 203
                        170       180       190       200       210       220       230       240
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 755538560 213 gvpqlVEPVLWDYGADL------DVHGKvfligkyqecGFQRLWAASAFKGATGASQalPPVEHHIRNHElwLQVAGSGP 286
Cdd:cd02742  204 -----VIVQYWDYDGDKynvelpEAAAK----------GFPVILSNGYYLDIFIDGA--LDARKVYKNDP--LAVPTPQQ 264
                        250
                 ....*....|..
gi 755538560 287 KDALQGIILTGW 298
Cdd:cd02742  265 KDLVLGVIACLW 276
Glyco_hydro_20 pfam00728
Glycosyl hydrolase family 20, catalytic domain; This domain has a TIM barrel fold.
64-203 4.79e-08

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


Pssm-ID: 425840  Cd Length: 344  Bit Score: 54.61  E-value: 4.79e-08
                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 755538560   64 YSPSEVTEILRLARLSELEVIPLVQTFGHM--------EFVLKHAAFAHLREVAL--FPNTLNPHEAESLALVQAMIDQI 133
Cdd:pfam00728  75 YTQEDIREIVAYAAARGIRVIPEIDMPGHAraalaaypELGCGCGADSPWVSVQWgpPEGQLNPGNEKTYTFLDNVFDEV 154
                          90       100       110       120       130       140       150
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*...
gi 755538560  134 LELHRDvRWLHIGCDEVyylgegeTSKQWLQQE--QNSHAKLCLSHMQAVAS------HVLTQHPGVTPLVWDDMLRD 203
Cdd:pfam00728 155 ADLFPS-DYIHIGGDEV-------PKGCWEKSPecQARMKEEGLKSLHELQQyfikraSKIVSSKGRRLIGWDEILDG 224
GH20_DspB_LnbB-like cd06564
Glycosyl hydrolase family 20 (GH20) catalytic domain of dispersin B (DspB), lacto-N-biosidase ...
7-201 1.75e-06

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.


Pssm-ID: 119334  Cd Length: 326  Bit Score: 49.59  E-value: 1.75e-06
                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 755538560   7 FKMRLVHLDLKGAPPKVSYlsevfplFHALGANGLLIEYEDMFPYEGHLRLLRAKHAYSPSEVTEILRLARLSELEVIPL 86
Cdd:cd06564   29 YKMNDLQLHLNDNLIFNLD-------DMSTTVNNATYASDDVKSGNNYYNLTANDGYYTKEEFKELIAYAKDRGVNIIPE 101
                         90       100       110       120       130       140       150       160
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 755538560  87 VQTFGHMEFVLKhaAFAHLREVALF----PNTLNPHEAESLALVQAMIDQILELHRDV-RWLHIGCDEvyYLGEGETSKQ 161
Cdd:cd06564  102 IDSPGHSLAFTK--AMPELGLKNPFskydKDTLDISNPEAVKFVKALFDEYLDGFNPKsDTVHIGADE--YAGDAGYAEA 177
                        170       180       190       200
                 ....*....|....*....|....*....|....*....|
gi 755538560 162 WLQqeqnshaklclsHMQAVASHVLTQhpGVTPLVWDDML 201
Cdd:cd06564  178 FRA------------YVNDLAKYVKDK--GKTPRVWGDGI 203
GH20_chitobiase-like cd06563
The chitobiase of Serratia marcescens is a beta-N-1,4-acetylhexosaminidase with a glycosyl ...
50-201 2.13e-04

The chitobiase of Serratia marcescens is a beta-N-1,4-acetylhexosaminidase with a glycosyl hydrolase family 20 (GH20) domain that hydrolyzes the beta-1,4-glycosidic linkages in oligomers derived from chitin. Chitin is degraded by a two step process: i) a chitinase hydrolyzes the chitin to oligosaccharides and disaccharides such as di-N-acetyl-D-glucosamine and chitobiose, ii) chitobiase then further degrades these oligomers into monomers. This GH20 domain family includes an N-acetylglucosamidase (GlcNAcase A) from Pseudoalteromonas piscicida and an N-acetylhexosaminidase (SpHex) from Streptomyces plicatus. SpHex lacks the C-terminal PKD (polycystic kidney disease I)-like domain found in the chitobiases. 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.


Pssm-ID: 119333  Cd Length: 357  Bit Score: 43.33  E-value: 2.13e-04
                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 755538560  50 PYEGHlrllrakhaYSPSEVTEILRLARLSELEVIPLVQTFGHM--------EFVLKHAAFAHLREVALFPNTLNPHEAE 121
Cdd:cd06563   78 PYGGF---------YTQEEIREIVAYAAERGITVIPEIDMPGHAlaalaaypELGCTGGPGSVVSVQGVVSNVLCPGKPE 148
                         90       100       110       120       130       140       150       160
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 755538560 122 SLALVQAMIDQILELHRDvRWLHIGCDEVYYlgegetsKQWLQQE--QNSHAKLCLSHMQAVASH-------VLTQHpGV 192
Cdd:cd06563  149 TYTFLEDVLDEVAELFPS-PYIHIGGDEVPK-------GQWEKSPacQARMKEEGLKDEHELQSYfikrvekILASK-GK 219

                 ....*....
gi 755538560 193 TPLVWDDML 201
Cdd:cd06563  220 KMIGWDEIL 228
GH20_chitobiase-like_1 cd06570
A functionally uncharacterized subgroup of the Glycosyl hydrolase family 20 (GH20) catalytic ...
27-206 2.27e-04

A functionally uncharacterized subgroup of the Glycosyl hydrolase family 20 (GH20) catalytic domain found in proteins similar to the chitobiase of Serratia marcescens, a beta-N-1,4-acetylhexosaminidase that hydrolyzes the beta-1,4-glycosidic linkages in oligomers derived from chitin. Chitin is degraded by a two step process: i) a chitinase hydrolyzes the chitin to oligosaccharides and disaccharides such as di-N-acetyl-D-glucosamine and chitobiose, ii) chitobiase then further degrades these oligomers into monomers. This subgroup lacks the C-terminal PKD (polycystic kidney disease I)-like domain found in the chitobiases. 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.


Pssm-ID: 119338  Cd Length: 311  Bit Score: 43.17  E-value: 2.27e-04
                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 755538560  27 SEVFPLFHALGANGLLieyedmfpyeghlrllrakhaYSPSEVTEILRLARLSELEVIPLVQTFGHM--------EFVLK 98
Cdd:cd06570   49 SKKYPKLQQKASDGLY---------------------YTQEQIREVVAYARDRGIRVVPEIDVPGHAsaiavaypELASG 107
                         90       100       110       120       130       140       150       160
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 755538560  99 HAAFAHLREVALFPNTLNPHEAESLALVQAMIDQILELHRDvRWLHIGCDEVYY--LGEGETSKQWLQQEQNSHAKLCLS 176
Cdd:cd06570  108 PGPYVIERGWGVFEPLLDPTNEETYTFLDNLFGEMAELFPD-EYFHIGGDEVDPkqWNENPRIQAFMKEHGLKDAAALQA 186
                        170       180       190
                 ....*....|....*....|....*....|.
gi 755538560 177 HMQAVASHVLTQHpGVTPLVWDDMLR-DIPQ 206
Cdd:cd06570  187 YFNQRVEKILSKH-GKKMIGWDEVLHpDLPK 216
GH20_HexA_HexB-like cd06562
Beta-N-acetylhexosaminidases catalyze the removal of beta-1,4-linked N-acetyl-D-hexosamine ...
25-201 3.88e-04

Beta-N-acetylhexosaminidases 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. The hexA and hexB genes encode the alpha- and beta-subunits of the two major beta-N-acetylhexosaminidase isoenzymes, N-acetyl-beta-D-hexosaminidase A (HexA) and beta-N-acetylhexosaminidase B (HexB). Both the alpha and the beta catalytic subunits have a TIM-barrel fold and belong to the glycosyl hydrolase family 20 (GH20). The HexA enzyme is a heterodimer containing one alpha and one beta subunit while the HexB enzyme is a homodimer containing two beta-subunits. Hexosaminidase mutations cause an inability to properly hydrolyze certain sphingolipids which accumulate in lysosomes within the brain, resulting in the lipid storage disorders Tay-Sachs and Sandhoff. Mutations in the alpha subunit cause in a deficiency in the HexA enzyme and result in Tay-Sachs, mutations in the beta-subunit cause in a deficiency in both HexA and HexB enzymes and result in Sandhoff disease. In both disorders GM(2) gangliosides accumulate in lysosomes. 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.


Pssm-ID: 119332 [Multi-domain]  Cd Length: 348  Bit Score: 42.58  E-value: 3.88e-04
                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 755538560  25 YLSEVFPLFHALGANGllieyedmfpyeghlrllrAKHAYSPSEVTEILRLARLSELEVIPLVQTFGHM--------EFV 96
Cdd:cd06562   47 LESPSYPELSKKGAYS-------------------PSEVYTPEDVKEIVEYARLRGIRVIPEIDTPGHTgswgqgypELL 107
                         90       100       110       120       130       140       150       160
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 755538560  97 LKHAAFAHLREVALFPNTLNPHEAESLALVQAMIDQILELHRDvRWLHIGCDEVY---YLGEGETsKQWLQQEQNSHAKL 173
Cdd:cd06562  108 TGCYAVWRKYCPEPPCGQLNPTNPKTYDFLKTLFKEVSELFPD-KYFHLGGDEVNfncWNSNPEI-QKFMKKNNGTDYSD 185
                        170       180
                 ....*....|....*....|....*...
gi 755538560 174 CLSHMQAVAsHVLTQHPGVTPLVWDDML 201
Cdd:cd06562  186 LESYFIQRA-LDIVRSLGKTPIVWEEVF 212
 
Blast search parameters
Data Source: Precalculated data, version = cdd.v.3.21
Preset Options:Database: CDSEARCH/cdd   Low complexity filter: no  Composition Based Adjustment: yes   E-value threshold: 0.01

References:

  • Wang J et al. (2023), "The conserved domain database in 2023", Nucleic Acids Res.51(D)384-8.
  • Lu S et al. (2020), "The conserved domain database in 2020", Nucleic Acids Res.48(D)265-8.
  • Marchler-Bauer A et al. (2017), "CDD/SPARCLE: functional classification of proteins via subfamily domain architectures.", Nucleic Acids Res.45(D)200-3.
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