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Metabolomics, also known as Metabolic Profiling, is an emerging discipline under the umbrella concept of systems biology. The goal of metabolomics is to know and understand the concentrations and fluxes of endogenous metabolites within a living biological system under study. General tools are being developed for the rapid measurement of many metabolites in a single experiment, most of which are mass spectrometric methods. FT-ICR has unique advantages, as a mass spectrometric method, in this regard. Applications of FT-ICR to metabolomics analyses will be discussed and reviewed in the context of the single publication currently available.

Peptide nucleic acids (PNA) incorporating nucleic acid bases into an achiral polyamide backbone bind to DNA in a sequence-dependent manner. The structure of a PNA-ribonucleic acid (RNA) complex was determined with nuclear magnetic resonance methods. A hexameric PNA formed a 1:1 complex with a complementary RNA that is an antiparallel, right-handed double helix with Watson-Crick base pairing similar to the "A" form structure of RNA duplexes. The achiral PNA backbone assumed a distinct conformation upon binding that differed from previously proposed models and provides a basis for further structure-based design of antisense agents.

Classical protein kinase C (PKC) family members are activated by the binding of various ligands to one of several cysteine-rich domains of the enzyme. The natural agonist, diacylglycerol (DAG), and the natural product superagonist, phorbol dibutyrate (PDB), activate the enzyme to produce wide-ranging physiological effects. The second cysteine-rich (Cys2) domain of rat brain PKC-gamma was expressed and labeled with 15N and 13C, and the solution structure was determined to high resolution using multidimensional heteronuclear NMR methods. The phorbol binding site was identified by titrating this domain with phorbol-12,13-dibutyrate (PDB) in the presence of organic cosolvents. Titrations of this domain with lipid micelles, in the absence and presence of phorbols, indicate selective broadening of some resonances. The observed behavior indicates conformational exchange between bound and free states upon protein-micelle interaction. The data also suggest that half of the domain, including the phorbol site and one of the zinc sites, is capable of inserting into membranes.

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