1WMY

Crystal Structure of C-type Lectin CEL-I from Cucumaria echinata

Summary for 1WMY

• Entry DOI: 10.2210/pdb1wmy/pdb
• Related: 1BCH 1BCJ 1BYF 1TLG 1WMZ
• Descriptor: lectin CEL-I, N-acetyl-D-galactosamine-specific C-type, CALCIUM ION, (4S)-2-METHYL-2,4-PENTANEDIOL, ... (4 entities in total)
• Functional Keywords: c-type lectin, n-acetylgalactosamine, invertebrate, sugar binding protein
• Biological source: Cucumaria echinata
• Total number of polymer chains: 2
• Total formula weight: 32569.34

Authors

Sugawara, H.,Kusunoki, M.,Kurisu, G.,Fujimoto, T.,Aoyagi, H.,Hatakeyama, T. (deposition date: 2004-07-22, release date: 2004-09-07, Last modification date: 2024-11-06)

Primary citation

Sugawara, H.,Kusunoki, M.,Kurisu, G.,Fujimoto, T.,Aoyagi, H.,Hatakeyama, T.
Characteristic Recognition of N-Acetylgalactosamine by an Invertebrate C-type Lectin, CEL-I, Revealed by X-ray Crystallographic Analysis
J.Biol.Chem., 279:45219-45225, 2004

PubMed Abstract: CEL-I is a C-type lectin, purified from the sea cucumber Cucumaria echinata, that shows a high specificity for N-acetylgalactosamine (GalNAc). We determined the crystal structures of CEL-I and its complex with GalNAc at 2.0 and 1.7 A resolution, respectively. CEL-I forms a disulfide-linked homodimer and contains two intramolecular disulfide bonds, although it lacks one intramolecular disulfide bond that is widely conserved among various C-type carbohydrate recognition domains (CRDs). Although the sequence similarity of CEL-I with other C-type CRDs is low, the overall folding of CEL-I was quite similar to those of other C-type CRDs. The structure of the complex with GalNAc revealed that the basic recognition mode of GalNAc was very similar to that for the GalNAc-binding mutant of the mannose-binding protein. However, the acetamido group of GalNAc appeared to be recognized more strongly by the combination of hydrogen bonds to Arg115 and van der Waals interaction with Gln70. Mutational analyses, in which Gln70 and/or Arg115 were replaced by alanine, confirmed that these residues contributed to GalNAc recognition in a cooperative manner.

PubMed: 15319425
DOI: 10.1074/jbc.M408840200

Experimental method

X-RAY DIFFRACTION (2 Å)