Complementary recognition

Homo-assembly of derivatives of the self-complementary recognition group 168 can only yield a linear ribbon or tape structure 179. This is indeed the case, as shown... 

The selective self-assembly of a receptor molecule with its complementary recognition unit in the presence of a competitive recognition unit has been described as self-sorting in the literature. DNA and RNA are the prime examples of this concept. Using the above-described copolymers containing two hydrogenbonding units, Burd and Week [95] were able to prove this concept of self-sorting also in synthetic polymer systems (Fig. 7.22). 

The sialylated derivative 36d74 showed a strong cross-linking ability with tetra-meric wheat germ agglutinin (WGA) with complementary recognition sites for sialosides. 

A principal function of the phosphorylated tsrosine sites on receptors is to recruit other proteins with complementary recognition sites. These can be enzymes, such as phospholipase C, or regulatory proteins and linkers of all kinds. 

Figure 5.12 Aspects of simple self-replication (a) two molecules form a covalent link (b) the new molecule templates replication through complementary recognition sites (c) mismatched functional groups fail to react (d) mismatched recognition sites fail to template a replicate molecule...

Bioaffinity recognition is based on non-catalytic complementary interaction with the analyte. The specificity of the complementary recognition process is mainly determined by the binding constant of the complex-formation reaction. The analyte quantification is usually done at equilibrium (when no further consumption of the analyte takes place) using a suitable transduction process modulated by the complementary recognition reaction. 

Giuseppone recently reported a proof-of-principle study featuring a library member exhibiting self-complementary recognition through hydrogen bonding [20], inspired by the Rebek replicator [21]. The authors mixed aldehydes 1-3 with amines 4 and 5 (Scheme 8.1). 

For reciprocal replicating systems, the situation is very different. The native reaction between the reacting partners proceeds with a rate Vuncat identical to the one found for the bimolecular reaction, since both building blocks bear identical recognition units and are therefore unable to associate with each other. Only addition of presynthesized template with two complementary recognition units allows reciprocal replication to take place. As a consequence, maximum rate Vcat is found at the start of the reaction and proved to be dependent on the amount of added template. In the case of strong duplex association, turn over of the catalyst is hampered by product inhibition and the curve shows a defined bend at the initial catalyst concentration and the rate of the reaction drops to the one found in the bimolecular experiment, Vuncat-... 

---