Structure-template specificity

Structure— template specificity Templates forming more than one structure ... 

In effect, a structural template, the aryl-substituted phenylalkylamines, was identified where no structural template had previously existed. Some of the agents, such as DOM, were known but it remained for them to be identified as being selective until the necessary pharmacological techniques were available— and, indeed, for several specific receptor populations to be identified and classified. However, normally, this is not the manner in which selective agents are developed. 

A large number of chemical and physical properties, manifest in the amino acid side chains, have been thoroughly examined by many investigators. Attempts have been made to correlate these properties with their relatedness among protein sequences. What is most relevant is how these side chains interact with the backbone and with one another and what roles they each play within particular types of secondary and tertiary structure. The parametric description of residue environments with the help of solvent accessibility, secondary structure, backbone torsion angles, pairwise residue-residue distances, or Ca positions is the comparison between amino acid types at protein sequence positions and residue locations in structural templates. A recent review has evaluated and quantified the extent to which the amino acid type-specific distributions of commonly used environment parameters discriminate with respect to the 20 amino acid types (Sunyaev et al., 1998). Some of the important amino acid properties and residue environments are discussed below. 

The experiments reported here demonstrate that the distamycin inhibition of DNA polymerase activities of FLV and MSV-M are template specific. Templates containing thymine and adenine are highly sensitive to the action of distamycins. This inhibition is dependent on the number of pyrrole rings in the molecule. The inhibition of DNA polymerases of RNA oncogenic viruses and the foci formation by distamycin derivatives conclude that both activities are dependent on the same structural component(s) of the molecule. 

Lewis, D.F.V, M. Dickins, P.J. Eddershaw, M.H. Tarbit, and P.S. Goldfarb (1999). Cytochrome P450 substrate specificities, substrate structural templates and enzyme active site geometries. Z)r g Metoio/. Drug Interact. 15, 1 9. 

Structure- type Typical template Specificity Templates Structure... 

The earliest use of in vitro selection schemes to isolate RNAs with novel phenotypes from pools of mutants were those of Spiegelman et al. [83]. In these experiments replicase, a template-specific RNA-directed polymerase, was used in a Darwinian selection system to isolate a structured RNA that had reduced affinity for the intercalating dye ethidium bromide. The mutant arose by sequential mutation during the course of the experiments, and was not a preexisting variant of the original RNA pool. 

Table 1.1 Material Synthesis of titanium-containing zeotype and Silicon Structure Metal source source ordered mesoporous materiais Template Specific information Crystallization conditions (temperature, time) Reference (first author, year)... 

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