Strict specificity for high-mannose type N-glycans and primary structure of a red alga Eucheuma serra lectin
| Autor: | Yuichiro Sato, Kaori Ito, Kanji Hori, Yasumasa Iwamoto, Yoshifumi Fujiwara, Hiroyuki Makino, Akihiro Kawakubo |
|---|---|
| Rok vydání: | 2007 |
| Předmět: |
Eucheuma
Glycan Myxococcus xanthus Molecular Sequence Data Biochemistry Substrate Specificity Glycolipid Bacterial Proteins Polysaccharides Amino Acid Sequence Peptide sequence chemistry.chemical_classification Edman degradation biology Sequence Homology Amino Acid Algal Proteins Protein primary structure Lectin biology.organism_classification Amino acid Mannose-Binding Lectins chemistry Carbohydrate Sequence Rhodophyta biology.protein Mannose Protein Binding |
| Zdroj: | Glycobiology. 17(5) |
| ISSN: | 0959-6658 |
| Popis: | We have elucidated the carbohydrate-binding profile of a non-monosaccharide-binding lectin named Eucheuma serra lectin (ESA)-2 from the red alga Eucheuma serra using a lectin-immobilized column and a centrifugal ultrafiltration-high performance liquid chromatography method with a variety of fluorescence-labeled oligosaccharides. In both methods, ESA-2 exclusively bound with high-mannose type (HM) N-glycans, but not with any of other N-glycans including complex type, hybrid type and core pentasaccharides, and oligosaccharides from glycolipids. These findings indicate that ESA-2 recognizes the branched oligomannosides of the N-glycans. However, ESA-2 did not bind with any of the free oligomannoses examined that are constituents of the branched oligomannosides implying that the portion of the core N-acetyl-D-glucosamine (GlcNAc) residue(s) of the N-glycans is also essential for binding. Thus, the algal lectin was strictly specific for HM N-glycans and recognized the extended carbohydrate structure with a minimum size of the pentasaccharide, Man(alpha1-3)Man(alpha1-6)Man(beta1-4)GlcNAc(beta1-4) GlcNAc. Kinetic analysis of binding with a HM heptasaccharide (M5) showed that ESA-2 has four carbohydrate-binding sites per polypeptide with a high association constant of 1.6x10(8) M-1. Sequence analysis, by a combination of Edman degradation and mass analyses of the intact protein and of peptides produced by its enzymic digestions, showed that ESA-2 is composed of 268 amino acids (molecular weight 27950) with four tandemly repeated domains of 67 amino acids. The number of repeats coincided with the number of carbohydrate-binding sites in the monomeric molecule. Surprisingly, the marine algal lectin was homologous to hemagglutinin from the soil bacterium Myxococcus xanthus. |
| Databáze: | OpenAIRE |
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