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Presents information on radiofrequency encoded combinatorial (REC) chemistry which is a developed nonchemical encoding strategy in library synthesis. Construction of encoded chemical libraries of complex molecular structures; Description of Taxol and its medicinal properties; Reference to the application of REC.

The discovery of catalytic RNAs (ribozymes) sparked scientific interest directed to the preparation of new biocatalysts. Analogous deoxyribozymes (catalytic DNAzymes) are not available in nature, but have been demonstrated synthetically. An interesting DNAzyme that revealed peroxidase-like activities is a complex between hemin and a single-stranded guanine-rich nucleic acid (aptamer). This complex catalyzed the oxidation of azino-bis(3-ethylbenzthi- azoline)-6-sulfonic acid, ABTS, by H202. It was suggested that the intercalation of hemin into the complex results in the formation of the biocatalyst.

: We recently showed that bitter melon-derived triterpenoids (BMTs) activate AMPK and increase GLUT4 translocation to the plasma membrane in vitro, and improve glucose disposal in insulin resistant models in vivo. Here we interrogated the mechanism by which these novel compounds activate AMPK, a leading anti-diabetic drug target. BMTs did not activate AMPK directly in an allosteric manner as AMP or the Abbott compound (A-769662) does, nor did they activate AMPK by inhibiting cellular respiration like many commonly used anti-diabetic medications. BMTs increased AMPK activity in both L6 myotubes and LKB1-deficient HeLa cells by 20–35%. Incubation with the CaMKKβ inhibitor, STO-609, completely attenuated this effect suggesting a key role for CaMKKβ in this activation. Incubation of L6 myotubes with the calcium chelator EGTA-AM did not alter this activation suggesting that the BMT-dependent activation was Ca2+-independent. We therefore propose that CaMKKβ is a key upstream kinase for BMT-induced activation of AMPK. [ABSTRACT FROM AUTHOR]