|PROSITE documentation PDOC00510
Glycosyl hydrolases family 10 active site
The microbial degradation of cellulose and xylans requires several types of
enzymes such as endoglucanases (EC 220.127.116.11), cellobiohydrolases (EC 18.104.22.168)
(exoglucanases), or xylanases (EC 22.214.171.124) [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 F  or as the glycosyl hydrolases
family 10 [4,E1]. The enzymes which are currently known to belong to this
family are listed below.
- Aspergillus awamori xylanase A (xynA).
- Bacillus sp. strain 125 xylanase (xynA).
- Bacillus stearothermophilus xylanase.
- Butyrivibrio fibrisolvens xylanases A (xynA) and B (xynB).
- Caldocellum saccharolyticum bifunctional endoglucanase/exoglucanase (celB).
This protein consists of two domains; it is the N-terminal domain, which
has exoglucanase activity, which belongs to this family.
- Caldocellum saccharolyticum xylanase A (xynA).
- Caldocellum saccharolyticum ORF4. This hypothetical protein is encoded in
the xynABC operon and is probably a xylanase.
- Cellulomonas fimi exoglucanase/xylanase (cex).
- Clostridium stercorarium thermostable celloxylanase.
- Clostridium thermocellum xylanases Y (xynY) and Z (xynZ).
- Cryptococcus albidus xylanase.
- Penicillium chrysogenum xylanase (gene xylP).
- Pseudomonas fluorescens xylanases A (xynA) and B (xynB).
- Ruminococcus flavefaciens bifunctional xylanase XYLA (xynA). This protein
consists of three domains: a N-terminal xylanase catalytic domain that
belongs to family 11 of glycosyl hydrolases; a central domain composed of
short repeats of Gln, Asn an Trp, and a C-terminal xylanase catalytic
domain that belongs to family 10 of glycosyl hydrolases.
- Streptomyces lividans xylanase A (xlnA).
- Thermoanaerobacter saccharolyticum endoxylanase A (xynA).
- Thermoascus aurantiacus xylanase.
- Thermophilic bacterium Rt8.B4 xylanase (xynA).
One of the conserved regions in these enzymes is centered on a conserved
glutamic acid residue which has been shown , in the exoglucanase from
Cellulomonas fimi, to be directly involved in glycosidic bond cleavage by
acting as a nucleophile. We have used this region as a signature pattern.
April 2006 / Pattern revised.
PROSITE method (with tools and information) covered by this documentation:
|GLYCOSYL_HYDROL_F10, PS00591; Glycosyl hydrolases family 10 active site (PATTERN)
E is the active site residue
|Sequences known to belong to this class detected by the pattern:
||ALL, except for Thermoascus aurantiacus xylanase whose sequence seems to be incorrect
|Other sequence(s) detected in Swiss-Prot:
|Matching PDB structures:
1B30 1B31 1B3V 1B3W ... [ALL]
||Gilkes N.R., Henrissat B., Kilburn D.G., Miller R.C. Jr., Warren R.A.J.
||Domains in microbial beta-1, 4-glycanases: sequence conservation, function, and enzyme families.
||Microbiol. Rev. 55:303-315(1991).
||Henrissat B., Claeyssens M., Tomme P., Lemesle L., Mornon J.-P.
||Cellulase families revealed by hydrophobic cluster analysis.
||A classification of glycosyl hydrolases based on amino acid sequence similarities.
||Biochem. J. 280:309-316(1991).
||Tull D., Withers S.G., Gilkes N.R., Kilburn D.G., Warren R.A.J., Aebersold R.
||Glutamic acid 274 is the nucleophile in the active site of a 'retaining' exoglucanase from Cellulomonas fimi.
||J. Biol. Chem. 266:15621-15625(1991).
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