Glycoside Hydrolase Family 33

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• Author: ^^^Tom Wennekes^^^
• Responsible Curator: ^^^Steve Withers^^^

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Glycoside Hydrolase Family GH33
Clan	GH-x
Mechanism	retaining/inverting
Active site residues	known/not known
CAZy DB link
http://www.cazy.org/GH33.html

Substrate specificities

Sialic acids, often known as N-acetylneuraminic acid (Neu5Ac, NANA, NeuNAc, NeuNA), are a family of nine carbon monosaccharides with a carboxylate group in the carbon 1 position that occupy the terminal position of the glycans, glycoproteins, glycolipids, and polysaccharides in cells and play important roles in interactions of the cell with its environment [1]. More than 50 sialic acid derivatives have been detected in eukaryotic and prokaryotic species; the most frequently detected sialic acids have an α(2,3) or α(2,6) linkage to galactose, N-acetylgalactosamine, and N-acetylglucosamine or an α(2,8) linkage to another sialic acids [2, 3, 4]. Sialic acids are hydrolyzed by sialidases (E.C. 3.2.1.18), and these enzymes are categorized into four different glycoside hydrolase(GH) families: GH33, GH34, and GH83 families are exosialidases while GH53 is an endosialidase [5].

This is an example of how to make references to a journal article [6]. (See the References section below). Multiple references can go in the same place like this [6, 7]. You can even cite books using just the ISBN [8]. References that are not in PubMed can be typed in by hand [9].

Kinetics and Mechanism

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Catalytic Residues

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Three-dimensional structures

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Family Firsts

First stereochemistry determination

Cite some reference here, with a short (1-2 sentence) explanation [6].

First catalytic nucleophile identification

Cite some reference here, with a short (1-2 sentence) explanation [9].

First general acid/base residue identification

Cite some reference here, with a short (1-2 sentence) explanation [7].

First 3-D structure

Cite some reference here, with a short (1-2 sentence) explanation [8].

References

1. Varki A (1997). Sialic acids as ligands in recognition phenomena. FASEB J. 1997;11(4):248-55. DOI:10.1096/fasebj.11.4.9068613 |
2. Kim S, Oh DB, Kang HA, and Kwon O. (2011). Features and applications of bacterial sialidases. Appl Microbiol Biotechnol. 2011;91(1):1-15. DOI:10.1007/s00253-011-3307-2 |
3. Varki A (2007). Glycan-based interactions involving vertebrate sialic-acid-recognizing proteins. Nature. 2007;446(7139):1023-9. DOI:10.1038/nature05816 |
4. Vimr ER, Kalivoda KA, Deszo EL, and Steenbergen SM. (2004). Diversity of microbial sialic acid metabolism. Microbiol Mol Biol Rev. 2004;68(1):132-53. DOI:10.1128/MMBR.68.1.132-153.2004 |
5. Buschiazzo A and Alzari PM. (2008). Structural insights into sialic acid enzymology. Curr Opin Chem Biol. 2008;12(5):565-72. DOI:10.1016/j.cbpa.2008.06.017 |
6. Comfort DA, Bobrov KS, Ivanen DR, Shabalin KA, Harris JM, Kulminskaya AA, Brumer H, and Kelly RM. (2007). Biochemical analysis of Thermotoga maritima GH36 alpha-galactosidase (TmGalA) confirms the mechanistic commonality of clan GH-D glycoside hydrolases. Biochemistry. 2007;46(11):3319-30. DOI:10.1021/bi061521n |
7. He S and Withers SG. (1997). Assignment of sweet almond beta-glucosidase as a family 1 glycosidase and identification of its active site nucleophile. J Biol Chem. 1997;272(40):24864-7. DOI:10.1074/jbc.272.40.24864 |
8. Robert V. Stick and Spencer J. Williams. (2009) Carbohydrates. Elsevier Science.

9. Sinnott, M.L. (1990) Catalytic mechanisms of enzymic glycosyl transfer. Chem. Rev. 90, 1171-1202. DOI: 10.1021/cr00105a006