Glycoside hydrolasesEC3.2.1. 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.[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]
This family contains
sialidases (
CAZY GH_33), which hydrolyse alpha-(2->3)-, alpha-(2->6)-, alpha-(2->8)-glycosidic linkages of terminal sialic residues in
oligosaccharides,
glycoproteins,
glycolipids, colominic acid and synthetic substrates. Sialidases may act as
pathogenic factors in
microbial infections.[8] The 1.8
A structure of trans-sialidase from
leech (Macrobdella decora, Q27701) 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.[9]
^Rothe B, Rothe B, Roggentin P, Schauer R (April 1991). "The sialidase gene from Clostridium septicum: cloning, sequencing, expression in Escherichia coli and identification of conserved sequences in sialidases and other proteins". Molecular & General Genetics. 226 (1–2): 190–7.
doi:
10.1007/BF00273603.
PMID2034213.
S2CID21308462.