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Exploring the cross-reactivity of S25-2: complex with a 5,6-dehydro-Kdo disaccharide.

ABSTRACT: The near-germline antibody S25-2 exhibits a remarkable cross-reactivity for oligosaccharides containing the bacterial lipopolysaccharide carbohydrate 3-deoxy-D-manno-oct-2-ulosonic acid (Kdo). The recent synthesis of a variety of Kdo analogues permits a detailed structural analysis of the importance of specific interactions in antigen recognition by S25-2. The Kdo disaccharide analogue Kdo-(2?4)-5,6-dehydro-Kdo lacks a 5-OH group on the second Kdo residue and has been cocrystallized with S25-2. The structure reveals that the modification of the Kdo residue at position 5 results in a rearrangement of intramolecular hydrogen bonds in the antigen that allows it to assume a novel conformation in the antibody-combining site. The cross-reactive binding of S25-2 to this synthetic ligand highlights the adaptability of this antibody to non-natural synthetic analogues.

SUBMITTER: Brooks CL

PROVIDER: S-EPMC3539693 | biostudies-literature | 2013 Jan

REPOSITORIES: biostudies-literature

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Exploring the cross-reactivity of S25-2: complex with a 5,6-dehydro-Kdo disaccharide.

Brooks Cory L CL Wimmer Kurt K Kosma Paul P Müller-Loennies Sven S Brade Lore L Brade Helmut H Evans Stephen V SV

Acta crystallographica. Section F, Structural biology and crystallization communications 20121225 Pt 1

The near-germline antibody S25-2 exhibits a remarkable cross-reactivity for oligosaccharides containing the bacterial lipopolysaccharide carbohydrate 3-deoxy-D-manno-oct-2-ulosonic acid (Kdo). The recent synthesis of a variety of Kdo analogues permits a detailed structural analysis of the importance of specific interactions in antigen recognition by S25-2. The Kdo disaccharide analogue Kdo-(2→4)-5,6-dehydro-Kdo lacks a 5-OH group on the second Kdo residue and has been cocrystallized with S25-2. ...[more]

PMID: 23295476

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