Home | Contact

The microbial degradation of cellulose and xylans requires several types of enzymes such as endoglucanases (EC 3.2.1.4), cellobiohydrolases (EC 3.2.1.91) (exoglucanases), or xylanases (EC 3.2.1.8) [1,2]. Fungi and bacteria produces a spectrum of cellulolytic enzymes (cellulases) and xylanases which, on the basis of sequence similarities, can be classified into families. One of these families is known as the cellulase family D [3] or as the glycosyl hydrolases family 8 [4,E1]. The enzymes which are currently known to belong to this family are listed below.

• Acetobacter xylinum endonuclease cmcAX.
• Bacillus strain KSM-330 acidic endonuclease K (Endo-K).
• Cellulomonas josui endoglucanase 2 (celB).
• Cellulomonas uda endoglucanase.
• Clostridium cellulolyticum endoglucanases C (celcCC).
• Clostridium thermocellum endoglucanases A (celA).
• Erwinia chrysanthemi minor endoglucanase y (celY).
• Bacillus circulans β-glucanase (EC 3.2.1.73).
• Escherichia coli hypothetical protein yhjM.

The most conserved region in these enzymes is a stretch of about 20 residues that contains two conserved aspartate. The first asparatate is thought [5] to act as the nucleophile in the catalytic mechanism. We have used this region as a signature pattern.

Henrissat B.

November 1997 / Text revised.

PROSITE method (with tools and information) covered by this documentation:

GLYCOSYL_HYDROL_F8, PS00812; Glycosyl hydrolases family 8 signature  (PATTERN)

Consensus pattern: A-[ST]-D-[AG]-D-x(2)-[IM]-A-x-[SA]-[LIVM]-[LIVMG]-x-A-x(3)-[FW] The first D is an active site residue Sequences known to belong to this class detected by the pattern: ALL Other sequence(s) detected in Swiss-Prot: NONE.

• Retrieve an alignment of Swiss-Prot true positive hits:   Clustal format, color, condensed view  / Clustal format, color  / Clustal format, plain text  / Fasta format • Retrieve the sequence logo from the alignment • Taxonomic tree view of all Swiss-Prot/TrEMBL entries matching PS00812 • Retrieve a list of all Swiss-Prot/TrEMBL entries matching PS00812 • Scan Swiss-Prot/TrEMBL entries against PS00812 • view ligand binding statistics

Matching PDB structures: 1CEM 1IS9 1KWF 1WZZ ... [ALL]

1	Authors	Beguin P.
	Title	Molecular biology of cellulose degradation.
	Source	Annu. Rev. Microbiol. 44:219-248(1990).
	PubMed ID	2252383
	DOI	10.1146/annurev.mi.44.100190.001251

2	Authors	Gilkes N.R., Henrissat B., Kilburn D.G., Miller R.C. Jr., Warren R.A.J.
	Title	Domains in microbial beta-1, 4-glycanases: sequence conservation, function, and enzyme families.
	Source	Microbiol. Rev. 55:303-315(1991).
	PubMed ID	1886523

3	Authors	Henrissat B., Claeyssens M., Tomme P., Lemesle L., Mornon J.-P.
	Title	Cellulase families revealed by hydrophobic cluster analysis.
	Source	Gene 81:83-95(1989).
	PubMed ID	2806912

4	Authors	Henrissat B.
	Title	A classification of glycosyl hydrolases based on amino acid sequence similarities.
	Source	Biochem. J. 280:309-316(1991).
	PubMed ID	1747104

5	Authors	Alzari P.M., Souchon H., Dominguez R.
	Title	The crystal structure of endoglucanase CelA, a family 8 glycosyl hydrolase from Clostridium thermocellum.
	Source	Structure 4:265-275(1996).
	PubMed ID	8805535

E1
Source	http://www.uniprot.org/docs/glycosid

PROSITE is copyright. It is produced by the SIB Swiss Institute Bioinformatics. There are no restrictions on its use by non-profit institutions as long as its content is in no way modified. Usage by and for commercial entities requires a license agreement. For information about the licensing scheme send an email to

Prosite License or see: prosite_license.html.


View entry in original PROSITE document format
View entry in raw text format (no links)

SIB Swiss Institute of Bioinformatics | Disclaimer