Glycoside Hydrolase Family 20

Known Activities	β-hexosaminidase (EC 3.2.1.52); lacto-N-biosidase (EC 3.2.1.140); β-1,6-N-acetylglucosaminidase) (EC 3.2.1.-); β-6-SO3-N-acetylglucosaminidase (EC 3.2.1.-)
Mechanism	Retaining
Clan	GH-K
3D Structure Status	( β / α ) ₈
Catalytic Nucleophile/Base	carbonyl oxygen of C-2 acetamido group of substrate
Catalytic Proton Donor	Glu
External resources	CAZypedia; HEXAdb; HEXBdb; HOMSTRAD; InterPro; PFAM; PRINTS; Tay-Sachs Disease;
Statistics	GenBank accession (1335); Uniprot accession (725); PDB accession (40); 3D entries (12); cryst (1)

Summary

All (1093) Archaea (4) Bacteria (897) Eukaryota (192) Structure (12 - 1 cryst) Characterized (100)

Bacteria
Protein Name	EC#	Organism	GenBank	Uniprot	PDB/3D
dispersin B / β-1,6-N-acetylglucosaminidase (DspB)	3.2.1.-	Actinobacillus pleuropneumoniae IA1	AAT46094.1	Q6GYA5
chitobiase (NagA1)	3.2.1.52	Aeromonas caviae CB101	CAH55822.1	Q659J9
chitobiase	3.2.1.52	Aeromonas hydrophila	AAG28494.1	Q9F9B4
β-N-acetylglucosaminidase (NagA;Nag-A) (Nag20A)	3.2.1.52	Aeromonas hydrophila SUWA-9	BAD00143.1	Q75V90
β-N-acetylglucosaminidase (NagB;Nag-B)	3.2.1.52	Aeromonas hydrophila SUWA-9	BAF76001.1	A7M7B5
β-N-acetylglucosaminidase	3.2.1.52	Aeromonas sp. 10S-24	BAA92145.1	Q9LC82
dispersin B / β-1,6-N-acetylglucosaminidase (DspB)	3.2.1.-	Aggregatibacter actinomycetemcomitans CU1000	AAP31025.1	Q840G9	1YHT[A]
chitobiase (Chb;ArChb)	3.2.1.52	Arthrobacter sp. TAD20	CAB72127.1	Q9L448
lacto-N-triose II β-N-acetylhexosaminidase (BbhI)	3.2.1.52	Bifidobacterium bifidum JCM 1254	BAI94822.1
β-N-acetylhexosaminidase (BbhII)	3.2.1.52	Bifidobacterium bifidum JCM 1254	BAI94823.1
lacto-N-biosidase (LnbB)	3.2.1.140	Bifidobacterium bifidum JCM 1254	ABZ78855.1	B3TLD6
β-N-acetylhexosaminidase (Hex20) (Hex20A)	3.2.1.52	Cellulomonas fimi ATCC 484	AAQ05800.1	Q7WUL4
β-N-acetylglucosaminidase (Nag1)	3.2.1.52	Enterobacter sp. G-1	BAA74506.1	Q9ZN69
endo-N-glycosidase (EndoE;EF0114)	3.2.1.52	Enterococcus faecalis V583	AAO79989.1 AAR59794.1 AAR59795.1 NP_813917.1
N-acetyl β-glucosaminidase	3.2.1.52	Lactobacillus casei ATCC 27092	BAA76352.1	Q9WXH9
β-hexosaminidase (Hex1T)	3.2.1.52	Paenibacillus sp. TS12	BAI63641.1	D2KW09	3GH4[A] 3GH5[A] 3GH7[A]
β-N-acetylglucosaminidase (NahA;PG0043)	3.2.1.52	Porphyromonas gingivalis W83	AAQ65295.1 CAA55582.1 NP_904396.1	P49008
mucin-desulfating glycosidase / sulfoglycosidase / β-6-SO3-N-acetylglucosaminidase (Sgl)	3.2.1.-	Prevotella sp. RS2	AAW30398.1	Q5MAH5
β-N-acetylhexosaminidase	3.2.1.52	proteobacterium AI21	ABE96869.1	A1XNE6
β-N-acetylglucosaminidase B (Nag096)	3.2.1.52	Pseudoalteromonas piscicida	BAA06136.1	P49007
β-N-acetylhexosaminidase (Hex86)	3.2.1.52	Pseudoalteromonas piscicida	BAB84321.1	Q8VUM1
transglycosylative enzyme (Hex99)	2.4.1.-	Pseudoalteromonas piscicida	BAA84281.1	Q9R6Y9
β-N-acetylglucosaminidase A (NagA)	3.2.1.52	Pseudoalteromonas piscicida	BAB17855.1	Q9FAC5
β-N-acetylglucosaminidase (ChiP)	3.2.1.52	Pseudoalteromonas sp. S9 / S91	AAC83238.1	Q9ZH38
β-N-acetylglucosaminidase 20B (HexB;Sde_3271) (Hex20B)	3.2.1.52	Saccharophagus degradans 2-40	ABD82526.1 ACG81707.1 DAA01339.1	Q7PC48
β-N-acetylglucosaminidase 20A (HexA; Sde_3037) (Hex20A)	3.2.1.52	Saccharophagus degradans 2-40	ABD82294.1 ACG81706.1 DAA01338.1	Q7PC49
chitobiase (Chb;Ctb;SmCHB)	3.2.1.52	Serratia marcescens 2170	AAB03808.1	Q54468	1C7S[A] 1C7T[A] 1QBA[A] 1QBB[A]
β-N-acetylglucosaminidase (GcnA)	3.2.1.52	Streptococcus gordonii FSS2	AAS02154.1	Q6ST21	2EPK[X] 2EPL[X] 2EPM[X] 2EPN[A,B] 2EPO[A,B]
β-N-acetylglucosaminidase (StrH)	3.2.1.52	Streptococcus pneumoniae ATCC 12213	AAC41450.1
β-N-acetylglucosaminidase (StrH)	3.2.1.52	Streptococcus pneumoniae ATCC 12213	AAC41450.1
β-N-acetylhexosaminidase (StrH;spr0057)	3.2.1.52	Streptococcus pneumoniae R6	AAK98861.1 NP_357651.1	Q8DRL6	3RPM[A,B]
β-N-acetylhexosaminidase (StrH;spr0057)	3.2.1.52	Streptococcus pneumoniae R6	AAK98861.1 NP_357651.1	Q8DRL6	3RPM[A,B]
β-N-acetylglucosaminidase (StrH;SP0057;SP_0057)	3.2.1.52	Streptococcus pneumoniae TIGR4	AAK74246.1 NP_344606.1	P49610	2YL6[A] 2YL8[A] 2YLL[A]
β-N-acetylglucosaminidase (StrH;SP0057;SP_0057)	3.2.1.52	Streptococcus pneumoniae TIGR4	AAK74246.1 NP_344606.1	P49610	2YL5[A,B,C,D] 2YL9[A,B,C,D] 2YLA[A,B,C,D]
β-N-acetylhexosaminidase (Hex56)	3.2.1.52	Streptomyces olivaceoviridis	CAC34802.1	Q9ACN7
β-N-acetylglucosaminidase (Hex;SpHex)	3.2.1.52	Streptomyces plicatus	AAC38798.3	O85361	1HP4[A] 1HP5[A] 1JAK[A] 1M01[A] 1M03[A] 1M04[A]
lacto-N-biosidase	3.2.1.140	Streptomyces sp. 142	AAD10478.1 AAE24545.1	Q9Z4I7
β-N-acetylglucosaminidase C (NagC)	3.2.1.52	Streptomyces thermoviolaceus OPC-520	BAC76622.1	Q83WL6
N-acetyl β-glucosaminidase (NagB)	3.2.1.52	Streptomyces thermoviolaceus OPC-520	BAA88762.2	Q9RHV6
β-N-acetylglucosaminidase (HexA)	3.2.1.52	Tannerella forsythia ATCC 43037	AAO33832.1	Q84FS9
N-acetylhexosaminidase (ExoI)	3.2.1.52	Vibrio furnissii	AAC44672.1 AAE36540.1	P96155
β-N-acetylglucosaminidase (Nag1;VhNag1)	3.2.1.52	Vibrio harveyi 650	ADJ68332.1	D9ISD9
β-N-acetylglucosaminidase (Nag2;VhNag2)	3.2.1.52	Vibrio harveyi 650	ADJ68333.1	D9ISE0
N-acetyl β-glucosaminidase (Chb)	3.2.1.52	Vibrio harveyi B392	AAA88682.1 AAR60429.1 AAX00633.1 CAD26692.1	P13670.1
N-acetyl β-glucosaminidase (Chb)	3.2.1.52	Vibrio parahaemolyticus ATCC 27969	AAA65915.1	Q60081
N-acetyl β-glucosaminidase (Hex)	3.2.1.52	Vibrio vulnificus ATCC 27562	AAA27527.1	Q04786
β-N-acetylglucosaminidase (NagA;YPTB1123)	3.2.1.52	Yersinia pseudotuberculosis IP 32953	CAH20363.1
Eukaryota
Protein Name	EC#	Organism	GenBank	Uniprot	PDB/3D
β-N-acetylhexosaminidase 2 (Hexo2;AtHex1;At1g05590) (plasma membrane)	3.2.1.52	Arabidopsis thaliana	AAD30612.1 AEE27861.1 NP_172050.1	Q9SYK0
β-N-acetylhexosaminidase (Hexo3;AtHex3;At1g65590) (plasma membrane)	3.2.1.52	Arabidopsis thaliana	AAB60911.1 AAM91092.1 AAN33206.1 AEE34399.1 NP_176737.2	O04477 Q8L7S6
β-N-acetylhexosaminidase 1 (Hexo1;AtHex2;At3g55260) (vacuolar)	3.2.1.52	Arabidopsis thaliana	AAM61367.1 AAN41320.1 AEE79360.1 BAE99290.1 CAB75760.1 CAM35467.1 NP_191086.1 NP_567017.1	Q0WUA8 Q8LFK0 Q9M3C5
N-acetylglucosaminidase (NagA;AN1502.2)	3.2.1.52	Aspergillus nidulans FGSC A4	BAB13330.1 EAA63815.1	C8VMN3
β-N-acetylhexosaminidase (HexA)	3.2.1.52	Aspergillus oryzae CCF 1066	AAM13977.1		cryst
β-N-acetylglucosaminidase (NagA;HexA;AO090005000639)	3.2.1.52	Aspergillus oryzae RIB40	BAC41255.1 BAE55679.1	Q8J2T0
N-acetyl-β-D-glucosaminidase (Nag1;Cr-Nag1)	3.2.1.52	Bionectria ochroleuca IK726 IBT 9371	ABC73393.1	A2SW08
β-N-acetylglucosaminidase	3.2.1.52	Bombyx mandarina	AAG48701.1	Q9GPG8
processing β-N-acetylglucosaminidase (Fdl)	3.2.1.52	Bombyx mori	ACV89846.1 ACV89847.1 BAJ20189.1	D3GGI8
chitooligosaccharidolytic β-N-acetylglucosaminidase	3.2.1.52	Bombyx mori	AAC60521.1	P49010
β-N-acetylglucosaminidase 1 (GlcNAcase1)	3.2.1.52	Bombyx mori W1-PND	BAF52531.1	A4PHN6
β-N-acetylglucosaminidase 2 (GlcNAcase2)	3.2.1.52	Bombyx mori W1-PND	BAF52532.1	A4PHN7
processing β-N-acetylhexosaminidase (Hex-1;T14F9.3)	3.2.1.52	Caenorhabditis elegans Bristol N2	AAA91263.1 CAO72174.1 CCD68941.1 NP_508409.1	Q22492
processing β-N-acetylhexosaminidase (Hex-2;C14C11.3)	3.2.1.52	Caenorhabditis elegans Bristol N2	AAA96105.3 CAO72175.1 CAO72175.2 CCD64497.1	Q17977
processing β-N-acetylhexosaminidase (Hex-4;Y51F10.5)	3.2.1.52	Caenorhabditis elegans Bristol N2	AAL35732.2 CAO72177.1 CCD73477.2	A7DY68
processing β-N-acetylhexosaminidase (Hex-5;Y70D2A.2)	3.2.1.52	Caenorhabditis elegans Bristol N2	CAA22078.2 CAO72178.1	Q9XW90
processing β-N-acetylhexosaminidase (Hex-3;Y39A1C.4)	3.2.1.52	Caenorhabditis elegans Bristol N2	CAA19506.2 CAA19506.3 CAI06053.1 CAI06053.2 CAO72176.1	Q9XXE8
N-acetyl β-glucosaminidase (Hex1)	3.2.1.52	Candida albicans A72	AAA34346.2	P43077
β-D-N-acetylhexosaminidase 1 (β-Hex)	3.2.1.52	Capsicum annuum	ADU20405.1
β-N-acetylglucosaminidase	3.2.1.52	Choristoneura fumiferana	AAX94571.1	Q52H16
β-N-acetylhexosaminidase / chitobiase (Hex1;CpHEX1)	3.2.1.52	Coccidioides posadasii SILVEIRA	ABB18373.1	Q309C3
N-acetyl β-glucosaminidase (α-chain) (NagA)	3.2.1.52	Dictyostelium discoideum	AAA33230.1	P13723.1
β-N-acetylhexosaminidase 2 / b(2)-subunit (Hexo2;Hex2;CG1787)	3.2.1.52	Drosophila melanogaster	AAF46406.1 AAM48390.1 NP_525081.1	Q9W3C4
β-N-acetylhexosaminidase 1 / b(1)-subunit (Hexo1;Hex1;CG1318)	3.2.1.52	Drosophila melanogaster	AAF47881.1 AAG22248.1 AAL28566.1 AAM49995.1 AAN11596.1 AAN11597.1 AAN11597.2 ACU43551.1 NP_523924.1 NP_728974.1 NP_728975.1 NP_728976.1	Q0E8H9 Q8IRB6 Q8MSS9 Q95S03 Q9VZE3
processing β-N-acetylglucosaminidase / α-subunit (Fdl;CG8824;Dmel_CG8824)	3.2.1.52	Drosophila melanogaster	AAF58500.2 AAL55992.1 AAM29423.1 AAM68691.1 AAM68691.2 AAM68692.1 AAM68693.1 ABY20426.1 NP_610790.1 NP_725178.2 NP_725179.1 NP_725180.1	Q8WSF3.1
β-N-acetylglucosaminidase A (Hex-A;Bex-1)	3.2.1.52	Entamoeba histolytica HM-1:IMSS	AAA80165.1 CAE46968.1 CAG23943.1	P49009
N-acetyl β-glucosaminidase (β-chain)	3.2.1.52	Felis catus	AAB30707.2 AAB67612.1 AEP60131.1	O18795 P49614
β-N-acetylglucosaminidase / β-hexosaminidase A (α-chain) (HexA)	3.2.1.52	Homo sapiens	AAA51827.1 AAB00965.1 AAD13932.1 AAH01138.2 AAH18927.1 AAH21030.1 AAH84537.1 AAQ70000.1 ACM85216.1 BAD96222.1 BAG59159.1 BAG60039.1 BAG62619.1 BAG62730.1 CAH10482.1 NP_000511.1	P06865.1 Q9BVJ8	2GJX[A,D,E,H] 2GK1[A,C,E,G]
β-N-acetylglucosaminidase B (β-chain) (HexB)	3.2.1.52	Homo sapiens	AAA51828.1 AAA51829.1 AAA52645.1 AAA68620.1 AAH17378.1 AAM46114.1 AAP88921.1 AAV48875.1 NP_000512.1	P07686.3	1NOU[A,B] 1NOW[A,B] 1NP0[A,B] 1O7A[A,B,C,D,E,F] 2GJX[B,C,F,G] 2GK1[B,D,F,H] 3LMY[A,B]
exo-chitinase 1 (Exc1)	3.2.1.52	Hypocrea lixii	AAB47060.1	P78738
exo-chitinase 2 (Exc2)	3.2.1.52	Hypocrea lixii	AAB47061.1	P78739
hexosaminidase (Exc1y)	3.2.1.52	Hypocrea lixii T-Y	CAC85402.1	Q8NIN7
hexosaminidase (Exc2y)	3.2.1.52	Hypocrea lixii T-Y	CAC85401.1	Q8NIN6
β-hexosaminidase (short fragment)	3.2.1.52	Lagenorhynchus acutus	AAF98706.1 AAF98707.1	Q9GJW3
β-hexosaminidase (short fragment)	3.2.1.52	Lagenorhynchus obliquidens	AAF98688.1 AAF98689.1 AAF98690.1 AAF98691.1 AAF98692.1 AAF98693.1 AAF98694.1 AAF98695.1 AAF98696.1	Q9GJW1
β-hexosaminidase (short fragment)	3.2.1.52	Lagenorhynchus obscurus	AAF98697.1 AAF98698.1 AAF98699.1 AAF98700.1 AAF98701.1 AAF98702.1 AAF98703.1 AAF98704.1 AAF98705.1	Q9GJW2
β-N-acetylglucosaminidase	3.2.1.52	Litopenaeus vannamei	ACR23316.1	C4P6W6
β-N-acetylglucosaminidase	3.2.1.52	Manduca sexta	AAQ97603.1	Q6UJX7
N-acetyl β-glucosaminidase (α-chain)	3.2.1.52	Mus musculus	AAA18775.1 AAA18777.1 AAC53246.1 AAH10755.1 BAC36036.1 BAC36049.1 BAC38018.1 BAE25744.1 BAE29566.1 BAE30831.1 BAE34808.1 BAE35394.1 BAE35457.1 BAE35636.1 BAE39189.1 BAE40146.1 CAA45615.1 NP_034551.1	P29416.1 Q8BNS6 Q91XG3
N-acetyl β-glucosaminidase (β-chain)	3.2.1.52	Mus musculus	AAA18776.1 AAA74738.1 AAB60667.1 BAE30155.1 BAE34846.1 BAE34877.1 BAE35874.1 BAE40652.1 CAA68781.1 NP_034552.1	P20060.2 Q3TXR9
N-acetylglucosaminidase	3.2.1.52	Neotyphodium sp. FCB-2004	AAU29327.1	Q643Y1
β-N-acetylhexosaminidase (Hex1;OfHex1)	3.2.1.52	Ostrinia furnacalis	ABI81756.1	Q06GJ0	3NSM[A] 3NSN[A] 3OZO[A] 3OZP[A]
β-N-acetylhexosaminidase (NagA;Hex;Pen ch 20)	3.2.1.52	Penicillium chrysogenum	AAF00010.1 AAP66194.1 AAQ80154.1	Q02352 Q9URR8
β-N-acetylhexosaminidase (Hex;PoHex)	3.2.1.52	Penicillium oxalicum CCF 1959 / CCF 3438	ABY57948.1	E3NYM0
β-N-acetylglucosaminidase 3 (HexA;Hex)	3.2.1.52	Spodoptera frugiperda	ABA27426.1 ABB76926.1 ABY57947.1	Q3LS76
β-N-acetylglucosaminidase 2 (HexB;Hex)	3.2.1.52	Spodoptera frugiperda	ABA27427.1 ABB76925.1	Q3LS75
β-N-acetylglucosaminidase 1	3.2.1.52	Spodoptera frugiperda	ABB76924.1	Q2Q1D3
processing β-N-acetylglucosaminidase (Fdl)	3.2.1.52	Spodoptera frugiperda	ACA30398.1	B1P868
β-N-acetylhexosaminidase (HexB)	3.2.1.52	Sus scrofa	BAI47712.1 CAA63123.1	Q29548
β-hexosaminidase (Bhex)	3.2.1.52	Tetrahymena thermophila	CAD55811.1	Q8IEV5
β-N-acetylglucosaminidase (Nag1;Chit73)	3.2.1.52	Trichoderma atroviride P1	AAB50829.1	P87258
β-N-acetylglucosaminidase (Nag2) (fragment)	3.2.1.52	Trichoderma atroviride P1	ABC95196.1	Q0ZLH7
exochitinase 2 (Zm.15748;ZmExo2;LOC100280178;ZM_BFb0204B20)	3.2.1.52	Zea mays B73	ACF87335.1 ACG29631.1 ACL54323.1	B4FYZ2

Footnotes

Experimental characterization exclusively covers enzyme activities at present. If you are aware of any missing experimental characterization that should be mentioned here, we encourage you to send your comment and support of the experimental evidence, including an electronic copy or appropriate link to the support material (i.e., article(s), thesis, database, etc), to cazy@afmb.univ-mrs.fr.