Glycoside Hydrolase Family 49

This page is currently under construction. This means that the Responsible Curator has deemed that the page's content is not quite up to CAZypedia's standards for full public consumption. All information should be considered to be under revision and may be subject to major changes.

• Author: ^^^Takashi Tonozuka^^^
• Responsible Curator: ^^^Takashi Tonozuka^^^

---

Glycoside Hydrolase Family GHnn
Clan	GH-N
Mechanism	inverting
Active site residues	known
CAZy DB link
http://www.cazy.org/fam/GHnn.html

Substrate specificities

Content is to be added here.

This is an example of how to make references to a journal article [1]. (See the References section below). Multiple references can go in the same place like this [1, 2]. You can even cite books using just the ISBN [3]. References that are not in PubMed can be typed in by hand [4].

Glycoside hydrolases of family 49 cleave α-1,6-linkages or α-1,4-linkages of polysaccharides containing α-1,6-linkages, dextran and pullulan. The major activities reported for this family of glycoside hydrolases are dextranase (EC 3.2.1.11). Dextran 1,6-α-isomaltotriosidase (EC 3.2.1.95) and isopullulanase (EC 3.2.1.57) activities have also been described.

Kinetics and Mechanism

Family GH49 α-glycosidases are inverting enzymes, as first shown by NMR on a dextranase Dex49A from Penicillium minioluteum.

Catalytic Residues

Content is to be added here.

Three-dimensional structures

Content is to be added here.

Family Firsts

First stereochemistry determination

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

First catalytic nucleophile identification

Cite some reference here, with a short (1-2 sentence) explanation [4].

First general acid/base residue identification

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

First 3-D structure

Cite some reference here, with a short (1-2 sentence) explanation [3].

References

1. 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 |
2. 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 |
3. Robert V. Stick and Spencer J. Williams. (2009) Carbohydrates. Elsevier Science.

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