Topological Defects in Hyperbranched Glycopolymers Enhance Binding to Lectins

Area of Science:

• Carbohydrate chemistry
• Biophysics
• Toxicology

Background:

• Synthetic multivalent carbohydrates are crucial for understanding biological interactions.
• The binding affinity of these molecules depends on scaffold topology and carbohydrate density.
• Ricinus communis agglutinin (RCA120) serves as a model plant toxin for studying carbohydrate-protein interactions.

Purpose of the Study:

• To investigate the impact of central scaffold topology and carbohydrate density on the binding mechanism and potency of synthetic multivalent carbohydrate systems.
• To compare poly- versus monodisperse carbohydrate systems.
• To determine the influence of protein receptor density on the preference for heterogeneous glycoconjugate presentations.

Main Methods:

• Surface plasmon resonance (SPR) was used to measure binding kinetics and affinity.
• Dynamic light scattering (DLS) was employed to characterize the size and dispersity of the carbohydrate systems.
• Binding assays were performed against the model plant toxin, Ricinus communis agglutinin (RCA120).

Main Results:

• Central scaffold topology and carbohydrate density significantly influence binding potency.
• Polydisperse carbohydrate systems demonstrated different binding characteristics compared to monodisperse systems.
• Lower densities of protein receptors favored the use of heterogeneous, polydisperse glycoconjugate presentations.

Conclusions:

• The presentation of carbohydrates (poly- versus monodisperse) is critical for effective binding to protein targets.
• Heterogeneous, polydisperse glycoconjugates are advantageous in environments with low protein receptor density.
• These findings provide insights into the design of synthetic carbohydrate-based ligands for specific biological applications.