PDBsum entry: 2cov

Sugar binding protein

PDB id: 2cov

Contents

Protein chains

92 a.a.

87 a.a.

Waters ×571

PDB id:

2cov

Name:

Sugar binding protein

Title:

Crystal structure of cbm31 from beta-1,3-xylanase

Structure:

Beta-1,3-xylanase. Chain: d, e, f, g, h, i. Fragment: carbohydrate-binding module, residues 378-469. Engineered: yes

Source:

Alcaligenes sp.. Organism_taxid: 118970. Strain: xy-234. Expressed in: escherichia coli. Expression_system_taxid: 562.

Biol. unit:

Hexamer (from PQS)

Resolution:

1.25Å R-factor: 0.151 R-free: 0.175

Authors:

H.Hashimoto,Y.Tamai,F.Okazaki,Y.Tamaru,T.Shimizu,T.Araki,M.S

Key ref:

H.Hashimoto et al. (2005). The first crystal structure of a family 31 carbohydrate-binding module with affinity to beta-1,3-xylan. FEBS Lett, 579, 4324-4328. PubMed id: 16061225 DOI: 10.1016/j.febslet.2005.06.062

Date:

18-May-05 Release date: 13-Sep-05

Protein chains

Q8RS40  (3XYN_ALCSP) -  Beta-1,3-xylanase

Seq: 469 a.a.

Struc: 92 a.a.

Protein chains

Q8RS40  (3XYN_ALCSP) -  Beta-1,3-xylanase

Seq: 469 a.a.

Struc: 87 a.a.

Enzyme reactions

• Enzyme class: Chains D, E, F, G, H, I: E.C.3.2.1.32 - Endo-1,3-beta-xylanase.
• Reaction: Random hydrolysis of 1,3-beta-D-xylosidic linkages in 1,3-beta-D-xylans.

 Gene Ontology (GO) functional annotation 

• Biochemical function: xylan endo-1,3-beta-xylosidase activity (1 term)

DOI no: 10.1016/j.febslet.2005.06.062

FEBS Lett 579:4324-4328 (2005)

PubMed id: 16061225

The first crystal structure of a family 31 carbohydrate-binding module with affinity to beta-1,3-xylan.

H.Hashimoto, Y.Tamai, F.Okazaki, Y.Tamaru, T.Shimizu, T.Araki, M.Sato.

ABSTRACT

Here, we present the crystal structure of the family 31 carbohydrate-binding module (CBM) of beta-1,3-xylanase from Alcaligenes sp. strain XY-234 (AlcCBM31) determined at a resolution of 1.25A. The AlcCBM31 shows affinity with only beta-1,3-xylan. The AlcCBM31 molecule makes a beta-sandwich structure composed of eight beta-strands with a typical immunoglobulin fold and contains two intra-molecular disulfide bonds. The folding topology of AlcCBM31 differs from that of the large majority of other CBMs, in which eight beta-strands comprise a beta-sandwich structure with a typical jelly-roll fold. AlcCBM31 shows structural similarity with CBM structures of family 34 and family 9, which also adopt structures based on immunoglobulin folds.

Selected figure(s)

Figure 2.
Fig. 2. Ribbon representation and topology diagram of monomeric AlcCBM31 are shown in (a) and (b). Secondary structures are labeled. Two disulfide bonds (SS-1 and SS-2) are shown as green colored sticks. Solvent-exposed aromatic residues are shown as ball-and-stick models. The colors of β-strands are corresponding to those in (a). Ribbon representations of CBM34 and CBM9 are shown in (c) and (e), respectively. Secondary structures of both polypeptides were assigned by the program DSSP [15]. β-Strands colored pink and pale blue are formed into the immunoglobulin fold with these colors corresponding to the AlcCBM31 structure. Topology diagrams of CBM34 and CBM9 are shown in (d) and (f), respectively.

Figure 4.
Fig. 4. Molecular surface of AlcCBM31. Exposed tyrosines and tryptophan are colored by orange and magenta, respectively.

The above figures are reprinted by permission from the Federation of European Biochemical Societies: FEBS Lett (2005, 579, 4324-4328) copyright 2005.

Figures were selected by an automated process.