Summary: Glycosyl hydrolases family 18
This is the Wikipedia entry entitled "Glycoside hydrolase family 18". More...
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Glycoside hydrolase family 18 Edit Wikipedia article
|crystal structure of a native chitinase from aspergillus fumigatus yj-407|
Glycoside hydrolases EC 3.2.1. are a widespread group of enzymes that hydrolyse the glycosidic bond between two or more carbohydrates, or between a carbohydrate and a non-carbohydrate moiety. A classification system for glycoside hydrolases, based on sequence similarity, has led to the definition of >100 different families. This classification is available on the CAZy(http://www.cazy.org/GH1.html) web site, and also discussed at CAZypedia, an online encyclopedia of carbohydrate active enzymes. 
Some members of this family, CAZY GH_18, belong to the chitinase class II group which includes chitinase, chitodextrinase and the killer toxin of Kluyveromyces lactis. The chitinases hydrolyse chitin oligosaccharides. The family also includes various glycoproteins from mammals; cartilage glycoprotein and the oviduct-specific glycoproteins are two examples.
- ^ Henrissat B, Callebaut I, Mornon JP, Fabrega S, Lehn P, Davies G (1995). "Conserved catalytic machinery and the prediction of a common fold for several families of glycosyl hydrolases". Proc. Natl. Acad. Sci. U.S.A. 92 (15): 7090–7094. doi:10.1073/pnas.92.15.7090. PMC 41477. PMID 7624375. http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=41477.
- ^ Henrissat B, Davies G (1995). "Structures and mechanisms of glycosyl hydrolases". Structure 3 (9): 853–859. doi:10.1016/S0969-2126(01)00220-9. PMID 8535779.
- ^ Bairoch, A. "Classification of glycosyl hydrolase families and index of glycosyl hydrolase entries in SWISS-PROT". 1999.
- ^ Henrissat, B. and Coutinho P.M. "Carbohydrate-Active Enzymes server". 1999.
- ^ CAZypedia, an online encyclopedia of carbohydrate-active enzymes.
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Internal database links
|Similarity to PfamA using HHSearch:||DUF3142|
External database links
|HOMSTRAD:||Glyco_hydro_18 Glyco_hydro_18_D1 Glyco_hydro_18_D2|
This tab holds annotation information from the InterPro database.
InterPro entry IPR001223
O-Glycosyl hydrolases (EC) are a widespread group of enzymes that hydrolyse the glycosidic bond between two or more carbohydrates, or between a carbohydrate and a non-carbohydrate moiety. A classification system for glycosyl hydrolases, based on sequence similarity, has led to the definition of 85 different families [PUBMED:7624375, PUBMED:8535779]. This classification is available on the CAZy (CArbohydrate-Active EnZymes) web site.
Some members of this family, CAZY, belong to the chitinase class II group which includes chitinase, chitodextrinase and the killer toxin of Kluyveromyces lactis. The chitinases hydrolyse chitin oligosaccharides. The family also includes various glycoproteins from mammals; cartilage glycoprotein and the oviduct-specific glycoproteins are two examples.
The mapping between Pfam and Gene Ontology is provided by InterPro. If you use this data please cite InterPro.
|Molecular function||hydrolase activity, hydrolyzing O-glycosyl compounds (GO:0004553)|
|Biological process||carbohydrate metabolic process (GO:0005975)|
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Curation and family details
|Seed source:||Pfam-B_574 (release 2.1)|
|Number in seed:||165|
|Number in full:||8946|
|Average length of the domain:||279.40 aa|
|Average identity of full alignment:||18 %|
|Average coverage of the sequence by the domain:||59.57 %|
|HMM build commands:||
build method: hmmbuild -o /dev/null HMM SEED
search method: hmmsearch -Z 23193494 -E 1000 --cpu 4 HMM pfamseq
|Family (HMM) version:||23|
|Download:||download the raw HMM for this family|
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For those sequences which have a structure in the Protein DataBank, we use the mapping between UniProt, PDB and Pfam coordinate systems from the PDBe group, to allow us to map Pfam domains onto UniProt sequences and three-dimensional protein structures. The table below shows the structures on which the Glyco_hydro_18 domain has been found. There are 288 instances of this domain found in the PDB. Note that there may be multiple copies of the domain in a single PDB structure, since many structures contain multiple copies of the same protein seqence.
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