PDBsum entry 2kr2

Carbohydrate binding protein

PDB id: 2kr2

Contents

Protein chain

190 a.a. *

Ligands

BGC-GLC

* Residue conservation analysis

PDB id:

2kr2

Name:

Carbohydrate binding protein

Title:

Xenopus laevis malectin complexed with maltose (glcalpha1-4glc)

Structure:

Malectin-a. Chain: a. Fragment: unp residues 27-213. Engineered: yes

Source:

Xenopus laevis. Clawed frog,common platanna,platanna. Organism_taxid: 8355. Gene: mlec, mlec-a. Expressed in: escherichia coli. Expression_system_taxid: 562.

NMR struc:

20 models

Authors:

T.Schallus,K.Feher,C.Muhle-Goll

Key ref:

T.Schallus et al. (2010). Analysis of the specific interactions between the lectin domain of malectin and diglucosides. Glycobiology, 20, 1010-1020. PubMed id: 20466650

Date:

30-Nov-09 Release date: 14-Jul-10

Protein chain

Q6INX3  (MLECA_XENLA) -  Malectin-A from Xenopus laevis

Seq: 276 a.a.

Struc: 190 a.a.*

* PDB and UniProt seqs differ at 3 residue positions (black crosses)

Enzyme reactions

• Enzyme class: E.C.?

Glycobiology 20:1010-1020 (2010)

PubMed id: 20466650

Analysis of the specific interactions between the lectin domain of malectin and diglucosides.

T.Schallus, K.Fehér, U.Sternberg, V.Rybin, C.Muhle-Goll.

ABSTRACT

The endoplasmic reticulum malectin is a highly conserved protein in the animal kingdom that has no counterpart so far in lower organisms. We recently determined the structure of its conserved domain and found a highly selective binding to Glc(2)Man(9)GlcNAc(2), an intermediate of N-glycosylation. In our quest for putative ligands during the initial characterization of the protein, we noticed that the malectin domain is highly specific for diglucosides but quite tolerant towards the linkage of the glucosidic bond. To understand the molecular requirements for the observed promiscuity of the malectin domain, here we analyze the binding to a range of diglucosides through comparison of the protein chemical shift perturbation patterns and the saturation transfer difference spectra of the ligands including two maltose-mimicking drugs. A comparison of the maltose-bound structure of the malectin domain with the complex of the native ligand nigerose reveals why malectin is able to tolerate such a diversity of ligands.