Controlled flexibility, nucleic acids

The PPC allows the generation of NADPH reduction equivalents required for cell anabolism, and ribose 5-phosphate molecules for the synthesis of nucleic acids. Alternatively, ribose 5-phosphate can also be generated or transformed into fructose 6-phosphate or glyceraldehyde 3-phosphate, providing metabolic flexibility to the cell, in order to balance the fluxes through these pathways. The flux through the PPC is related to the nucleic acid requirements for DNA duplication or RNA transcription, and could probably be controlled by the cell cycle (Wagner, 1997). 

At an initial HUPO-PSI-sponsored meeting of this group it was decided that the approach to designing such a format should be multilayered, with Level 1 designed to fulfil basic requirements and be suitable for rapid implementahon. Subsequent levels will supply further complexity and flexibility, for example the ability to deal with other interactors such as nucleic acids. Wherever possible, the potential values of attributes in the data model are defined by controlled vocabularies researchers may also ascribe confidence levels to the data at various points throughout the data entry process and add free comments in appropriate places. 

Modern calorimetry has transformed and advanced to such a degree that today its acute sensitivity and flexibility has made it an indispensable tool throughout the life sciences. Ultrasensitive calorimetry now plays an integral role in biotechnology, providing researchers with essential information on the thermodynamics, structure, stability, and functionality of proteins, nucleic acids, lipids, and other biomolecules. Ultrasensitive calorimetry is a vital tool for R D in pharmaceuticals, genetics, energy, and materials—in almost any area where the measurement and controlled manipulation of substances and interactions are required at the molecular level. 

Calixarenes are regular macrocyclic aromatic systems, whose conformation can be largely controlled between the extremes of rigid defined molecular shapes and entirely flexible architectures. Upper and lower rim of cone-shaped calixarenes can be equipped with a large variety of functional groups, which may carry multiple charges. These features qualify calixarenes to be potential ligands for biomacromolecules such as proteins and nucleic acids. 

The size and structure of the PAMAM dendrimer family can be controlled easily and carefully. Although it was reported that heat-induced solvolysis of the perfect dendritic structure of PAMAM dendrimers was helpful for the enhancement of transfection efficiency, probably due to the more flexible structure [94], the highly controlled core-shell structure of PAMAM dendrimers can be a very attractive backbone for the detailed study of stmcture-fimction relationships in the polymeric delivery of nucleic acid drugs. The easy modification of surface functionalities should also facilitate various biomedical applications for PAMAM dendrimer derivatives. 

In recent years there has been a growing awareness in the scientific community that nucleic acids can exhibit a significant amount of conformational flexibility. The central cellular functions of replication, transcription, and translation involve alterations in the conformation of DNA and RNA. All the different steps in these processes involving nucleic acids, including control steps, indicate that the deformation of polynucleotide structure is intimately related to the biological role of nucleic acids. The conformational variants may exist for very long times (> 1 s) or may exist only transiently. Even those that exist only for a matter of nanoseconds may be functionally... 

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