Controlling Superselectivity of Multivalent Interactions with Cofactors and Competitors

Moieties that compete with multivalent interactions or act as cofactors are common in living systems, but their effect on multivalent binding remains poorly understood. We derive a theoretical model that shows how the superselectivity of multivalent interactions is modulated by the presence of cofactors or competitors. We find that the role of these participating moieties can be fully captured by a simple rescaling of the affinity constant of the individual ligand-receptor bonds. Theoretical predictions are supported by experimental data of the membrane repair protein annexin A5 binding to anionic lipid membranes in the presence of Ca2+ cofactors and of the extracellular matrix polysaccharide hyaluronan (HA) binding to CD44 cell surface receptors in the presence of HA oligosaccharide competitors. The obtained findings should facilitate understanding of multivalent recognition in biological systems and open new routes for fine-tuning the selectivity of multivalent nanoprobes in medicinal chemistry.

Automated summary

In this study, a theoretical model is derived to investigate the impact of cofactors or competitors on multivalent interactions. It is found that the effect of participating moieties can be accurately captured by rescaling the affinity constant of ligand-receptor bonds. Experimental data support the theoretical predictions and demonstrate the superselectivity of multivalent binding in the presence of cofactors or competitors.