In molecular biology, glycoside hydrolase family 7 is a family of glycoside hydrolases EC 3.2.1., which 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.[1][2][3] This classification is available on the CAZy web site,[4][5] and also discussed at CAZypedia, an online encyclopedia of carbohydrate active enzymes.[6][7]
| Glycosyl hydrolase family 7 | |||||||||
|---|---|---|---|---|---|---|---|---|---|
 endoglucanase i complexed with epoxybutyl cellobiose | |||||||||
| Identifiers | |||||||||
| Symbol | Glyco_hydro_7 | ||||||||
| Pfam | PF00840 | ||||||||
| Pfam clan | CL0004 | ||||||||
| InterPro | IPR001722 | ||||||||
| SCOP2 | 1cel / SCOPe / SUPFAM | ||||||||
| CAZy | GH7 | ||||||||
| CDD | cd07999 | ||||||||
| |||||||||
Glycoside hydrolase family 7 CAZY GH_7 comprises enzymes with several known activities including endoglucanase (EC 3.2.1.4) and cellobiohydrolase (EC 3.2.1.91). These enzymes were formerly known as cellulase family C.
Exoglucanases and cellobiohydrolases[8] play a role in the conversion of cellulose to glucose by cutting the disaccharide cellobiose from the non-reducing end of the cellulose polymer chain. Structurally, cellulases and xylanases frequently consist of a catalytic domain joined to a cellulose-binding domain (CBD) via a linker region that is rich in proline and/or hydroxy-amino acids. In type I exoglucanases, the CBD domain is found at the C-terminal extremity of these enzyme (this short domain forms a hairpin loop structure stabilised by 2 disulphide bridges).
References
edit- ^ Henrissat B, Callebaut I, Fabrega S, Lehn P, Mornon JP, Davies G (July 1995). "Conserved catalytic machinery and the prediction of a common fold for several families of glycosyl hydrolases". Proceedings of the National Academy of Sciences of the United States of America. 92 (15): 7090–4. Bibcode:1995PNAS...92.7090H. doi:10.1073/pnas.92.15.7090. PMC 41477. PMID 7624375.
- ^ Davies G, Henrissat B (September 1995). "Structures and mechanisms of glycosyl hydrolases". Structure. 3 (9): 853–9. doi:10.1016/S0969-2126(01)00220-9. PMID 8535779.
- ^ Henrissat B, Bairoch A (June 1996). "Updating the sequence-based classification of glycosyl hydrolases". The Biochemical Journal. 316 (Pt 2): 695–6. doi:10.1042/bj3160695. PMC 1217404. PMID 8687420.
- ^ "Home". CAZy.org. Retrieved 2018-03-06.
- ^ Lombard V, Golaconda Ramulu H, Drula E, Coutinho PM, Henrissat B (January 2014). "The carbohydrate-active enzymes database (CAZy) in 2013". Nucleic Acids Research. 42 (Database issue): D490–5. doi:10.1093/nar/gkt1178. PMC 3965031. PMID 24270786.
- ^ "Glycoside Hydrolase Family 7". CAZypedia.org. Retrieved 2018-03-06.
- ^ CAZypedia Consortium (December 2018). "Ten years of CAZypedia: a living encyclopedia of carbohydrate-active enzymes" (PDF). Glycobiology. 28 (1): 3–8. doi:10.1093/glycob/cwx089. PMID 29040563.
- ^ Gilkes NR, Henrissat B, Kilburn DG, Miller RC, Warren RA (June 1991). "Domains in microbial beta-1, 4-glycanases: sequence conservation, function, and enzyme families". Microbiological Reviews. 55 (2): 303–15. doi:10.1128/MMBR.55.2.303-315.1991. PMC 372816. PMID 1886523.
