Chemistry Reference
In-Depth Information
Figure 13.9 Phosphorus-containing dendrimer with 96 terminal chlorides; R is indicated by
the bold type in the structure.
groups at the remaining termini) were the most effective and that large generation den-
drimers [G(4)-G(6)] had more activity toward ConA than small generation dendri-
mers [G(1)-G(3); Woller et al. (2003)]. Glycodendrimers have recently been the
subject of several excellent reviews, and many more examples of biological systems
that have been studied using glycodendrimers are provided in several review articles
(Jayaraman et al. 1997; Roy 2003; Srinivas and Narayanaswamy 2005; Tsvetkov
and Nifantiev 2005; Matsuoka et al. 2006).
13.3. MULTIVALENCY
As noted, monovalent lectin-carbohydrate interactions are generally too weak to be
physiologically relevant. In order to achieve higher affinity interactions, multiple
carbohydrates may be clustered around each binding site. The proximity of many
carbohydrates to each binding site on the protein would slow the off rate of the inter-
action of a glycosystem with the lectin. A decrease in the off rate of the interaction
will cause an overall increase in the binding affinity of the system. Page and
Jencks (1971) refer to chelation effects in a critical discussion in this area, and Lee
and Lee (2000) articulate the idea of proximity effects well.
