2bt9
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LECTIN FROM RALSTONIA SOLANACEARUM COMPLEXED WITH ME-FUCOSIDE
OverviewOverview
Plant pathogens, like animal ones, use protein-carbohydrate interactions, in their strategy for host recognition, attachment, and invasion. The, bacterium Ralstonia solanacearum, which is distributed worldwide and, causes lethal wilt in many agricultural crops, was shown to produce a, potent L-fucose-binding lectin, R. solanacearum lectin, a small protein of, 90 amino acids with a tandem repeat in its amino acid sequence. In the, present study, surface plasmon resonance experiments conducted on a series, of oligosaccharides show a preference for binding to alphaFuc1-2Gal and, alphaFuc1-6Gal epitopes. Titration microcalorimetry demonstrates the, presence of two binding sites per monomer and an unusually high affinity, of the lectin for alphaFuc1-2Gal-containing oligosaccharides (KD = 2.5 x, 10(-7) M for 2-fucosyllactose). R. solanacearum lectin has been, crystallized with a methyl derivative of fucose and with the highest, affinity ligand, 2-fucosyllactose. X-ray crystal structures, the one with, alpha-methyl-fucoside being at ultrahigh resolution, reveal that each, monomer consists of two small four-stranded anti-parallel beta-sheets., Trimerization through a 3-fold or pseudo-3-fold axis generates a, six-bladed beta-propeller architecture, very similar to that previously, described for the fungal lectin of Aleuria aurantia. This is the first, report of a beta-propeller formed by oligomerization and not by sequential, domains. Each monomer presents two fucose binding sites, resulting in six, symmetrically arranged sugar binding sites for the beta-propeller., Crystals were also obtained for a mutated lectin complexed with a fragment, of xyloglucan, a fucosylated polysaccharide from the primary cell wall of, plants, which may be the biological target of the lectin.
About this StructureAbout this Structure
2BT9 is a Single protein structure of sequence from Ralstonia solanacearum with MFU as ligand. Structure known Active Site: AC1. Full crystallographic information is available from OCA.
ReferenceReference
The fucose-binding lectin from Ralstonia solanacearum. A new type of beta-propeller architecture formed by oligomerization and interacting with fucoside, fucosyllactose, and plant xyloglucan., Kostlanova N, Mitchell EP, Lortat-Jacob H, Oscarson S, Lahmann M, Gilboa-Garber N, Chambat G, Wimmerova M, Imberty A, J Biol Chem. 2005 Jul 29;280(30):27839-49. Epub 2005 May 27. PMID:15923179
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