Solid-phase synthesis for the identification of high-affinity bivalent lectin ligands.

Published

Journal Article

The development of carbohydrate-based therapeutics has been frustrated by the low affinities that characterize protein-carbohydrate complexation. Because of the oligomeric nature of most lectins, the use of multivalency may offer a successful strategy for the creation of high-affinity ligands. The solid-phase evaluation of libraries of peptide-linked multivalent ligands facilitates rapid examination of a large fraction of linker structure space. If such solid-phase assays are to replicate solution binding behavior, the potential for intermolecular bivalent binding on bead surfaces must be eliminated. Here we report the solid-phase synthesis and analysis of peptide-linked, spatially segregated mono- and bivalent ligands for the legume lectin concanavalin A. Bead shaving protocols were used for the creation of beads displaying spatially segregated binding sequences on the surface of Tentagel resins. The same ligands were also synthesized on PEGA resin to determine the effect of ligand presentation on solid-phase binding. While we set out to determine the lower limit of assay sensitivity, the unexpected observation that intermolecular bivalent ligand binding is enhanced for bivalent ligands relative to monovalent ligands allowed direct observation of the level of surface blocking required to prevent intermolecular bivalent ligand binding. For a protein with binding sites separated by 65 A, approximately 99.9% of Tentagel(1) surface sites and 99.99% of the total sites on a PEGA bead must be blocked to prevent intermolecular bivalent binding. We also report agglutination and calorimetric solution-phase binding studies of mono- and bivalent peptide-linked ligands.

Full Text

Duke Authors

Cited Authors

  • Debenham, SD; Snyder, PW; Toone, EJ

Published Date

  • July 2003

Published In

Volume / Issue

  • 68 / 15

Start / End Page

  • 5805 - 5811

PubMed ID

  • 12868911

Pubmed Central ID

  • 12868911

Electronic International Standard Serial Number (EISSN)

  • 1520-6904

International Standard Serial Number (ISSN)

  • 0022-3263

Digital Object Identifier (DOI)

  • 10.1021/jo0207271

Language

  • eng