Rigid scaffolds

An alternative approach is that adopted by Horrocks and co-workers, where the aromatic residues in metal-binding proteins are used as sensitizers. Since the distance between the metal and the donor is effectively fixed, this provides a rigid scaffold for the experiment, and the absence of a directly conjugated pathway between the metals means that Forster (through space) energy transfer can be assumed. The r-6 distance-dependence of this means that the extent of sensitized emission from the lanthanide ion provides information on the spatial relationship between the metal-ion binding site (lanthanide ions often bind at Ca2+ sites) and nearby aromatic residues. 58-60... 

Figure 14.3 Structures of Pateamine A (1), Boc-pateamine A (25), and DMDA-PatA (28). The putative binding (rigid regions, in red) and scaffolding (flexible and modifiable, in blue) domains are indicated and suggest possible sites for modification, namely, the C3- amino group.

Flexible Scaffolding Container Properties Rigid Surface Scaffolding... 

Figure 1.21 Periodic properties for poly(amidoamine) (PAMAM) dendrimers as a function of generation G = 0-10 (I) flexible scaffolding (G = 0-3) (II) container properties (G = 4-6) and (III) rigid surface scaffolding (G = 7-10) various chemo/ physical dendrimer surfaces amplified according to Z = NCN where Nc = core multiplicity, Nb = branch cell multiplicity, G = generation...

Fig. 7.9. The rigidity of the Cull scaffold is important for SCF E3 activity. Top, schematic diagram of the flexible linker Cull mutant. Bottom, the SCF containing the Cull linker mutant retains the ability to bind phosphoryl-...

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