Reviewed, UniProtKB/Swiss-Prot Q7WUL4 (HEX20_CELFI)

Names and origin

Protein names

Recommended name:
    Beta-N-acetylhexosaminidase
    EC=3.2.1.52
Alternative name(s):
    Beta-N-acetylglucosaminidase
    Beta-N-acetylgalactosaminidase
    Hex20

Gene names

Name:	hex20
Synonyms:	hex20A

Organism

Cellulomonas fimi

Taxonomic identifier

1708 [NCBI]

Taxonomic lineage

Bacteria › Actinobacteria › Actinobacteridae › Actinomycetales › Micrococcineae › Cellulomonadaceae › Cellulomonas

Protein attributes

Sequence length	496 AA.
Sequence status	Complete.
Protein existence	Evidence at protein level.

General annotation (Comments)

Function	Catalyzes the cleavage of beta-N-acetylglucosaminides and beta-N-acetylgalactosaminides. Also catalyzes the hydrolysis of N-acetylchitooligomers. May be involved in chitin degradation. It is not able to cleave beta-glucosides. Ref.1
Catalytic activity	Hydrolysis of terminal non-reducing N-acetyl-D-hexosamine residues in N-acetyl-beta-D-hexosaminides. Ref.1
Pathway	Glycan degradation; chitin degradation.
Miscellaneous	The reaction mechanism involves an oxazolinium ion intermediate.
Sequence similarities	Belongs to the glycosyl hydrolase 20 family.
Biophysicochemical properties	Kinetic parameters: There is a 4-fold greater activity on 4'-nitrophenyl beta-N-acetyl-D-glucosaminide than on 4'-nitrophenyl beta-N-acetyl-D-galactosaminide. KM=53 µM for 4'-nitrophenyl beta-N-acetyl-D-glucosaminide KM=66 µM for 4'-nitrophenyl beta-N-acetyl-D-galactosaminide pH dependence: Optimum pH is 7.3-8.7 with 4'-nitrophenyl beta-N-acetyl-D-glucosaminide as substrate. Rapidly inactivated above pH 9.5 and stable from pH 6.0 to 9.5.

Ontologies

Keywords
Biological process	Carbohydrate metabolism Chitin degradation Polysaccharide degradation
Molecular function	Glycosidase Hydrolase
Technical term	Direct protein sequencing
Gene Ontology (GO)
Biological process	chitin catabolic process Inferred from electronic annotation. Source: UniProtKB-KW
Molecular function	beta-N-acetylhexosaminidase activity Inferred from electronic annotation. Source: EC cation binding Inferred from electronic annotation. Source: InterPro
Complete GO annotation...

Sequence annotation (Features)

	Feature key	Position(s)	Length	Description	Graphical view	Feature identifier
Molecule processing
	Chain	1 – 496	496	Beta-N-acetylhexosaminidase		PRO_0000252455
Sites
	Active site	298	1	Proton donor By similarity

Sequences

	Sequence		Length	Mass (Da)
	Q7WUL4-1 [UniParc]. Last modified October 1, 2003. Version 1. Checksum: 7D514C614991706C	FASTA	496	53,326
	10 20 30 40 50 60 MPDVAVIPRP VLLETTDGPP FVLTAATILV VDSAPELVAV GVLAADLLGR LSGRPVEVRY 70 80 90 100 110 120 TEGGAPSVVR LRLSEDLPAG DEAYRLVVSE HRVDIDARSA AGLVRAVVTL RQTVSSLGDG 130 140 150 160 170 180 TLTVPALRVE DHPRYAWRGL SIDVARHFFT VDDLKAIIGL LAHYKLNVLH LHLTDDQGWR 190 200 210 220 230 240 VHLPSRPHLT RASAGTSVGG GPGGFYNPAQ LAEIVVARAA RGIRVVPEID VPGHVNAATH 250 260 270 280 290 300 AYGDLTPSGE PTDVYTGIEV GFSRLHDDLP ATRPFLRDVF TDLAAMTPGE YVHIGGDEVL 310 320 330 340 350 360 TMDHDKYARL VGYAASVVRD AGKKVVGWQE ISSTPLEPGT VVQYWDINAD PAPFVAAAQA 370 380 390 400 410 420 GAHVLMSPGS RAYLDMKYDA TTELGLEWAG HIELRDAYDW EPSTLIPGVP PESVIGVEAA 430 440 450 460 470 480 VWTETLTDLG ELTSMLLPRL AAVAEVAWTA PQDRDWDDFS GRVAQHAPFW DRVGFRWHAS 490 PQVSWPGPGS APGAAF

References

[1]

"Characterization of a beta-N-acetylhexosaminidase and a beta-N-acetylglucosaminidase/beta-glucosidase from Cellulomonas fimi." Mayer C., Vocadlo D.J., Mah M., Rupitz K., Stoll D., Warren R.A.J., Withers S.G. FEBS J. 273:2929-2941(2006) [PubMed: 16762038] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [GENOMIC DNA], PROTEIN SEQUENCE OF 1-10, FUNCTION, CATALYTIC ACTIVITY, BIOPHYSICOCHEMICAL PROPERTIES.

Cross-references

Sequence databases
EMBL GenBank DDBJ	AF478459 Genomic DNA. Translation: AAQ05800.1.
3D structure databases
HSSP	HSSP built from PDB template 1NOW based on UniProtKB P07686.
SMR	Q7WUL4. Positions 2-486.
ModBase	Search...
Protein family/group databases
CAZy	GH20. Glycoside Hydrolase Family 20.
Enzyme and pathway databases
BRENDA	3.2.1.52. 97800.
Family and domain databases
InterPro	IPR001540. Glyco_hydro_20. IPR015883. Glyco_hydro_20_cat-core. IPR017853. Glyco_hydro_catalytic_core. IPR013781. Glyco_hydro_sg_catalytic. [Graphical view]
Gene3D	G3DSA:3.20.20.80. Glyco_hydro_cat. 1 hit.
PANTHER	PTHR22600. Glyco_hydro_20. 1 hit.
Pfam	PF00728. Glyco_hydro_20. 1 hit. [Graphical view]
PRINTS	PR00738. GLHYDRLASE20.
ProtoNet	Search...

Entry information

Entry name

HEX20_CELFI

Accession

Primary (citable) accession number: Q7WUL4

Entry history

Integrated into UniProtKB/Swiss-Prot:	October 17, 2006
Last sequence update:	October 1, 2003
Last modified:	February 9, 2010
This is version 32 of the entry and version 1 of the sequence. [Complete history]

Entry status

Reviewed (UniProtKB/Swiss-Prot)

Annotation project

HAMAP (High-quality Automated and Manual Annotation of microbial Proteomes)