Biomolecular receptors

Accordingly, in Figure 8 sensitive layers can demonstrate either a higher reversibility or a higher selectivity. In combination with these properties, polymers usually show a high reversibility since they have poor selectivity and since they are relatively stable in contrast to biomolecular receptor layers where the selectivity and the sensitivity are high, but where the stability is rather poor as is reversibility. 

Many interesting processes take place on time scales far beyond the computer simulation times that can reasonably be obtained. The complexation of ligands to a biomolecular receptor molecule is an example of a process that would be prohibitively expensive to simulate. Using the concept of thermodynamic cycles, however, relative free energy differences can often be evaluated. This technique is especially useful because nonphysical mutations can be carried out in computer simulations. 

Examples of membrane conductance mediated by biomolecular/receptor interactions... 

Lyotropic lamellar (La) liquid crystals (LC), in a form of vesicle or planar membrane, are important for membrane research to elucidate both functional and structural aspects of membrane proteins. Membrane proteins so far investigated are receptors, substrate carriers, energy-transducting proteins, channels, and ion-motivated ATPases [1-11], The L liquid crystals have also been proved useful in the two-dimensional crystallization of membrane proteins[12, 13], in the fabrication of protein micro-arrays[14], and biomolecular devices[15]. Usefulness of an inverted cubic LC in the three-dimensional crystallization of membrane proteins has also been recognized[16]. 

Guanylate Cyclase Receptors and Biomolecular Targets Involved... 

Photoaffinity Labeling of Receptor Protein Tyrosine Kinases (PTK) and Biomolecular Targets Involved in the Signaling Pathways... 

This diverse set of biosensing experimental demonstrations illustrates the flexibility of the OFRR device. Nearly any biomolecular recognition event can be detected. The examples illustrated with the previously described experiments include DNA sequence detection and virus detection through surface proteins. Additional biosensing examples for which the OFRR is well-suited include site-specific cleavage, protein-protein interactions, and cell genotype/phenotype identification through receptors. Furthermore, as shown by the theory outlined above, the OFRR can be accurately and precisely quantitative. 

Selective agonist binding of AMPA and kainate receptors. P21, Biomolecular Interactions, Molecular Graphics and Modelling Society, Bristol UK, 3-5 April. 

Immunosensors have been developed commercially mostly for medical purposes but would appear to have considerable potential for food analysis. The Pharmacia company has developed an optical biosensor, which is a fully automated continuous-flow system which exploits the phenomenon of surface plasmon resonance (SPR) to detect and measure biomolecular interactions. The technique has been validated for determination of folic acid and biotin in fortified foods (Indyk, 2000 Bostrom and Lindeberg, 2000), and more recently for vitamin Bi2. This type of technique has great potential for application to a wide range of food additives but its advance will be linked to the availability of specific antibodies or other receptors for the various additives. It should be possible to analyse a whole range of additives by multi-channel continuous flow systems with further miniaturisation. 

Rouleau, N., Turcotte, S., Mondou, M.H., Roby, P. and Bosse, R. (2003) Development of a versatile platform for nuclear receptor screening using AlphaScreen. Journal of Biomolecular Screening,... 

Estrogen administration in postmenopausal women has been observed to produce cardioprotective benefits. The exact biomolecular mechanisms for this cardioprotection are unclear but it is likely that actions mediated both through the estrogen receptors, such as the beneficial alteration in lipid profiles and upregulation of the low-density lipoprotein (LDL) receptor, and independently of the estrogen receptors, such as antioxidant action, contribute to the observed cardioprotective effects of estrogens. 

Biological interactions between molecules are stereo-specific the fit in such interactions must be stereo-chemically correct. The three-dimensional structure of biomolecules large and small—the combination of configuration and conformation—is of the utmost importance in their biological interactions reactant with enzyme, hormone with its receptor on a cell surface, antigen with its specific antibody, for example (Fig. 1-22). The study of biomolecular stereochemistry with precise physical methods is an important part of modem research on cell structure and biochemical function. 

---