InterPro domain: IPR018077

O-Glycosyl hydrolases ( 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 glycosyl hydrolases, based on sequence similarity, has led to the definition of 85 different families [ 1 , 2 ]. This classification is available on the CAZy (CArbohydrate-Active EnZymes) website.

Glycoside hydrolase family 25 GH25 comprises enzymes with only one known activity; lysozyme ( 3.2.1.17 ).

It has been shown [ 3 , 4 ] that a number of cell-wall lytic enzymes are evolutionary related and can be classified into a single family.Two residues, an aspartate and a glutamate, have been shown [ 5 ] to beimportant for the catalytic activity of the Charalopsis enzyme. These residuesas well as some others in their vicinity are conserved in all proteins fromthis family.

1. Conserved catalytic machinery and the prediction of a common fold for several families of glycosyl hydrolases. Proc. Natl. Acad. Sci. U.S.A. 92, 7090-4
2. Structures and mechanisms of glycosyl hydrolases. Structure 3, 853-9
3. Sequence of the lyc gene encoding the autolytic lysozyme of Clostridium acetobutylicum ATCC824: comparison with other lytic enzymes. Gene 104, 25-31
4. A classification of glycosyl hydrolases based on amino acid sequence similarities. Biochem. J. 280 ( Pt 2), 309-16
5. The N,O-diacetylmuramidase of Chalaropsis species. Identificaiton of aspartyl and glutamyl residues in the active site. J. Biol. Chem. 253, 6787-93