{PDOC00622} {PS00776; GH11_1} {PS00777; GH11_2} {PS51761; GH11_3} {BEGIN} *********************************************************************************** * Glycosyl hydrolases family 11 (GH11) active sites signatures and domain profile * *********************************************************************************** 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 G [3] or as the glycosyl hydrolases family 11 (GH11) [4,E1,E2]. Family 11 is monospecific, only consisting of xylanases. The enzymes which are currently known to belong to this family are listed below. - Aspergillus awamori xylanase C (xynC). - Bacillus circulans, pumilus, stearothermophilus and subtilis xylanase (xynA). - Clostridium acetobutylicum xylanase (xynB). - Clostridium stercorarium xylanase A (xynA). - Fibrobacter succinogenes xylanase C (xynC) which consist of two catalytic domains that both belong to family 10. - Neocallimastix patriciarum xylanase A (xynA). - 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. - Schizophyllum commune xylanase A. - Streptomyces lividans xylanases B (xlnB) and C (xlnC). - Trichoderma reesei xylanases I and II. The GH11 domain folds into a jelly-roll shape likened to a partially closed right hand (see ). Several anti-parallel beta-strands bend almost 90 degrees to produce a substrate-binding groove characteristic of the GH11 domain active sites. Two catalytic Glu residues face each other from opposite sides of the groove. The hydrolysis reaction is believed to follow a double- displacement mechanism, with one Glu residue acting as a general acid/base catalyst and the other as a nucleophile. Two of the conserved regions in these enzymes are centered on glutamic acid residues which have both been shown [5], in Bacillus pumilis xylanase, to be necessary for catalytic activity. We have used both regions as signature patterns. We have also developed a profile that covers the entire GH11 domain. -Consensus pattern: [PSA]-[LQ]-x-E-[YF]-Y-[LIVM](2)-[DE]-x-[FYWHN] [E is an active site residue] -Sequences known to belong to this class detected by the pattern: ALL, except for Piromyces sp. xynA. -Other sequence(s) detected in Swiss-Prot: NONE. -Consensus pattern: [LIVMF]-x(2)-E-[AG]-[YWG]-[QRFGS]-[SG]-[STAN]-G-x-[SAF] [E is an active site residue] -Sequences known to belong to this class detected by the pattern: ALL, except for Piromyces sp. xynA. -Other sequence(s) detected in Swiss-Prot: 3. -Sequences known to belong to this class detected by the profile: ALL. -Other sequence(s) detected in Swiss-Prot: NONE. -Expert(s) to contact by email: Henrissat B.; bernie@afmb.cnrs-mrs.fr -Last update: June 2015 / Text revised; profile added. [ 1] Beguin P. "Molecular biology of cellulose degradation." Annu. Rev. Microbiol. 44:219-248(1990). PubMed=2252383; DOI=10.1146/annurev.mi.44.100190.001251 [ 2] 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). PubMed=1886523 [ 3] Henrissat B., Claeyssens M., Tomme P., Lemesle L., Mornon J.-P. "Cellulase families revealed by hydrophobic cluster analysis." Gene 81:83-95(1989). PubMed=2806912 [ 4] Henrissat B. "A classification of glycosyl hydrolases based on amino acid sequence similarities." Biochem. J. 280:309-316(1991). PubMed=1747104 [ 5] Ko E.P., Akatsuka H., Moriyama H., Shinmyo A., Hata Y., Katsube Y., Urabe I., Okada H. "Site-directed mutagenesis at aspartate and glutamate residues of xylanase from Bacillus pumilus." Biochem. J. 288:117-121(1992). PubMed=1359880 [ 6] Wan Q., Zhang Q., Hamilton-Brehm S., Weiss K., Mustyakimov M., Coates L., Langan P., Graham D., Kovalevsky A. "X-ray crystallographic studies of family 11 xylanase Michaelis and product complexes: implications for the catalytic mechanism." Acta Crystallogr. D 70:11-23(2014). PubMed=24419374; DOI=10.1107/S1399004713023626 [E1] https://www.uniprot.org/docs/glycosid [E2] http://www.cazy.org/GH11.html -------------------------------------------------------------------------------- PROSITE is copyrighted by the SIB Swiss Institute of Bioinformatics and distributed under the Creative Commons Attribution-NonCommercial-NoDerivatives (CC BY-NC-ND 4.0) License, see https://prosite.expasy.org/prosite_license.html -------------------------------------------------------------------------------- {END}