Multivalent binding

The definition of an association constant for an antibody—antigen reaction can become more complex if the antibody—antigen reaction iavolves a multivalent antigen, as is the case when a polyclonal antisemm is used for detection of an antigen. This type of multivalent binding is termed avidity and is defined by the equation ... 

Ebola-gp 1, or Dengue-gp E. DC-SIGN is also known to oligomerize, and it is therefore particularly important to understand the intrinsic binding and multivalent binding requirements of this lectin. 

Bis-hydrazide-containing molecules also can be used to activate soluble polymeric sub-stances-containing aldehyde groups. For instance, dextran may be periodate oxidized to create numerous formyl functionalities on each molecule. Subsequent reaction with a homobifunctional hydrazide in large excess results in a hydrazide-activated polymer having multivalent-binding capability toward aldehydes or ketones (Chapter 25, Section 2.2). Insoluble support matrices suitable for affinity chromatography have been activated in a similar fashion to create the hydrazide derivative (O Shannessy and Wilchek, 1990). 

Mulder. A.. Auletta. T., Sartori, A., Del Ciotto, S.. Casnati. A., Ungaro, R., Huskens. J. and Reinhoudt, D.N. (2004) Divalent binding of a bis(adamantyl)-functionalized calix[4]arene to beta-cyclodexti in-based hosts An experimental and theoretical study on multivalent binding in solution and at selfassembled monolayers. J. Am. Chem. Soc., 126,... 

Fig. 2.7.3. Cluster glycosides synthesized by Lee et al. and their binding to ASGPR on isolated rabbit hepatocytes [7], Carbohydrate residues involved in multivalent binding are highlighted in gray. The residual carbohydrates are assumed to function as a scaffold.

Multivalent Binding of Sugar-Decorated Vesicles to Lectins... 

SIGNIFICANCE OF MULTIVALENT BINDING INTERACTIONS IN BIOLOGICAL SYSTEMS... 

Because they are easily accessible, glycans displayed on the surface of mammalian cells provide enormous opportunities to bind to many microbial pathogens, ranging from viruses to molecular toxins and from pathogenic bacteria to parasites. In multivalent binding, multiple interactions between ligands and various receptors are common (Fig. 16.1). One representative example is ricin—a versatile and durable A-B-type toxin—in which one of the protein chains (the B chain) is a lectin that interacts and binds terminal galactose (Gal) on the surface of eukaryotic cells with multivalent interactions to facilitate entry of the other peptide chain (the A chain) into the cell to cause cellular death via the catalytic... 

FIGURE 16.1 Multivalent binding of a bacterium to the clustered carbohydrate ligand carrying matching terminal carbohydrate residue(s) found in the host cell surface. The multivalent interaction prevents the attachment of the bacterium to the host cell surface. The functional role of the linker is the optimal presentation of the glycan into the binding site of the receptor, but it may also be involved in additional hydrophobic contacts. 

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