Complexes molecular recognition

The nonionic template strategy based on hydrogen bonds and to a certain extent on n-n interactions has made catenanes and rotaxanes readily available. The molecular recognition and self-organization process which is responsible for the formation of intertwined and interlocked structures is founded upon the same weak interactions that govern many biological processes. Amide-based catenanes and rotaxanes can thus serve as valuable models for complex molecular recognition patterns in nature. 

Another important issue related to surface cycloaddition reactions is the stereochemistry of the products. Advances in this area may open new methods for developing new chemical sensors that may be used for complex molecular recognition tasks. In one study, Wolkow and coworkers54 showed that a scanning tunneling microscope can be used to determine the absolute chirality of individual molecules of cis- and trans-2-butene adsorbed on... 

Hunter CA, Misuraca MC, Turega SM. Dissection of complex molecular recognition interfaces. J Am Chem Soc. 2011 133 582-594. 

Stability and folding of proteins are closely connected both involve the complex molecular recognition of structural elements along the polypeptide chain. 

According to these basic concepts, molecular recognition implies complementary lock-and-key type fit between molecules. The lock is the molecular receptor and the key is the substrate that is recognised and selected to give a defined receptor—substrate complex, a coordination compound or a supermolecule. Hence molecular recognition is one of the three main pillars, fixation, coordination, and recognition, that lay foundation of what is now called supramolecular chemistry (8—11). 

Information may be stored in the architecture of the receptor, in its binding sites, and in the ligand layer surrounding the bound substrate such as specified in Table 1. It is read out at the rate of formation and dissociation of the receptor—substrate complex (14). The success of this approach to molecular recognition ties in estabUshing a precise complementarity between the associating partners, ie, optimal information content of a receptor with respect to a given substrate. 

Topology. This parameter may have reference to either the receptor as an individual molecular stmcture or to the receptor—substrate complex on a higher level of organization that is direcdy related to the mode and efficiency of molecular recognition (14,30). 

However, all the receptors hitherto discussed are monomolecular species which possess a monomolecular cavity, pocket, cleft, groove or combination of it including the recognition sites to yield a molecular receptor—substrate complex. They can be assembled and preserved ia solution although there are dependences (see below). By way of contrast, molecular recognition demonstrated ia the foUowiag comes from multimolecular assembly and organization of a nonsolution phase such as polymer materials and crystals. 

Molecular recognition of protein-ligand complexes and drug design 97CRV1369. 

V. Pichon, M. Bouzige, C. Miege and M. C. Hennion, Immunosorbents natural molecular recognition materials for sample preparation of complex environmental matrices . Trends. Anal. Chem. 18 219-235 (1999). 

Crystalline 1 1 complex formation can be regarded as molecular recognition in the process of crystallization. Since the formation of a new type of the crystalline 1 1 complex depends on the shapes of R7 and R8 35), the influence of the spatial relationship between R7 and R8 on the complex formation was investigated. 

Kurimura, Y. Macromolecule-Metal Complexes — Reactions and Molecular Recognition. Vol. 90, pp. 105-138. 

Finally, to produce the structural and functional devices of the cell, polypeptides are synthesized by ribosomal translation of the mRNA. The supramolecular complex of the E. coli ribosome consists of 52 protein and three RNA molecules. The power of programmed molecular recognition is impressively demonstrated by the fact that aU of the individual 55 ribosomal building blocks spontaneously assemble to form the functional supramolecular complex by means of noncovalent interactions. The ribosome contains two subunits, the 308 subunit, with a molecular weight of about 930 kDa, and the 1590-kDa 50S subunit, forming particles of about 25-nm diameter. The resolution of the well-defined three-dimensional structure of the ribosome and the exact topographical constitution of its components are still under active investigation. Nevertheless, the localization of the multiple enzymatic domains, e.g., the peptidyl transferase, are well known, and thus the fundamental functions of the entire supramolecular machine is understood [24]. 

Bohm HI, Klebe G. What can we learn from molecular recognition in protein-ligand complexes for the design of new drugs Angew Chem Int Ed Engl 1996 35 2589-614. 

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