Complementary recognition sites

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...

FIG. 20 DNA duplex 20 used for studies regarding the protein-modulated DNA electron transfer. Methyltransferase M.Hhal is capable of binding to the shadowed recognition site between two oxidizable 5 -GG-3 sites (outlined letters). The complementary strand of the duplex contains the Rh intercalator, [Rh(phi)2bpy ], at its 5 end, which can function as a photooxidant. (Adapted from Ref. 168.)... 

Rotaxanes are made of dumbbell-shaped and ring components which exhibit some kind of interaction originating from complementary chemical properties. In rotaxanes containing two different recognition sites in the dumbbell-shaped component it is possible to switch the position of the ring between the two stations by an external stimu-... 

There is one separate tRNA for each amino acid and one separate specific synthetase. The enzyme must bind not only the correct amino acid but also the correct tRNA, so that each synthetase has specific recognition sites for both. Transfer RNAs contain a three-base sequence that is an anticodon, which binds to its complementary codon on messenger RNA. The importance of the synthetase in relation to fidelity of translating the information in messenger RNA is indicated by the fact that, once an amino acid is bound to tRNA, its identity as an amino acid is dictated by the anticodon site on the transfer RNA and not by the amino acid itself. (The enzyme can be considered as a dictionary, since it provides a cross-reference between the nucleic acid and amino acid languages.)... 

Considering tridentate sites, 2,6-diaminopyridine and uracil are complementary single site groups (see Sections 9.4.2 and 9.4.3 below). On the other hand barbituric acid (BA) and 2,4,6-triaminopyrimidine (TAP) or -triazine (TAT) are Janus molecules containing two identical recognition sites while 168 is plerotopic by virtue of its two complementary sites (see Section 9.4.4). 

Generally, two different procedures have been adopted for preparation of MIPs. They involve either covalent or non-covalent complex formation of a template and complementary monomers with apt functional groups. [19]. Co-polymerization of this complex with a cross-linking monomer in a porogenic solvent solution, followed by removal of the template, results in formation of the porous polymer material with recognition sites complementary in size and shape to molecules of the target compound that can next be determined as an analyte. 

The technique of molecular imprinting was successfully used to create a polymer with specific recognition sites. [9] A template was used to organise monomers during the polymerisation process. After the polymerisation, it was washed away from the insoluble network, leaving behind domains of complementary size and shape (Scheme 10). 

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