Glycoside hydrolase family 33
In molecular biology, glycoside hydrolase family 33 is a family of glycoside hydrolases.
Glycoside hydrolases 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 web site, and also discussed at CAZypedia, an online encyclopedia of carbohydrate active enzymes.
This family contains sialidases, which hydrolyse alpha--, alpha--, alpha--glycosidic linkages of terminal sialic residues in oligosaccharides, glycoproteins, glycolipids, colominic acid and synthetic substrates. Sialidases may act as pathogenic factors in microbial infections. The 1.8 A structure of trans-sialidase from leech in complex with 2-deoxy-2, 3-didehydro-NeuAc was solved. The refined model comprising residues 81-769 has a catalytic beta-propeller domain, a N-terminal lectin-like domain and an irregular beta-stranded domain inserted into the catalytic domain.
