1 research outputs found
Probing Carbohydrate-Lectin Recognition in Heterogeneous Environments with Monodisperse Cyclodextrin-Based Glycoclusters
A series of Ī²-cyclodextrin (Ī²CD)-scaffolded
glycoclusters
exposing heterogeneous yet perfectly controlled displays of Ī±-mannosyl
(Ī±-Man) and Ī²-lactosyl (Ī²-Lact) antennas were synthesized
to probe the mutual influence of varying densities of the saccharide
motifs in the binding properties toward different plant lectins. Enzyme-linked
lectin assay (ELLA) data indicated that the presence of Ī²-Lact
residues reinforced binding of Ī±-Man to the mannose-specific
lectin concanavalin A (Con A) even though homogeneous Ī²-Lact
clusters are not recognized at all by this lectin, supporting the
existence of synergic recognition mechanisms (<i>heterocluster
effect</i>). Conversely, the presence of Ī±-Man motifs in
the heteroglycoclusters also resulted in a binding-enhancing effect
of Ī²-Lact toward peanut agglutinin (PNA), a lectin strongly
binding multivalent lactosides but having no detectable affinity for
Ī±-mannopyranosides, for certain architectural arrangements.
Two-site, sandwich-type ELLA data corroborated the higher lectin clustering
efficiency of heterogeneous glycoclusters compared with homogeneous
displays of the putative sugar ligand with identical valency. A turbidity
assay was also consistent with the previous observations. Most revealingly,
the lectin cross-linking ability of heterogeneous glycoclusters was
sensitive to the presence of high concentrations of the non-ligand
sugar, strongly suggesting that āmismatchingā saccharide
motifs may modulate carbohydrate-lectin specific recognition in a
lectin-dependent manner when present in highly dense displays together
with the āmatchingā ligand, a situation frequently encountered
in biological systems