Conformational possibilities of a series of deoxyguanosine analogues possessing or lacking antiviral activity were evaluated using methods of the molecular mechanics. Comparison of the spatial structures of acyclic analogues with one another and with the spatial structures of deoxyguanosine demonstrates restricted conformational mobility for compounds devoid of activity. The level of sterically...

Polyadenylate (poly(A)) has the ability to form a parallel duplex with Hoogsteen adenine:adenine base pairs at low pH or in the presence of ammonium ions. In order to evaluate the potential of this structural motif for nucleic acid-based nanodevices, we characterized the effects on duplex stability of substitutions of the ribose sugar with 2'-deoxyribose, 2'-O-methyl-ribose, 2'-deoxy-2'-fluoro-...

We have investigated the conformations of the hexadeoxyribonucleotide, L-d(CGCGCG) composed of L-deoxyribose, the mirror image molecule of natural D-deoxyribose. In this paper, we report the synthesis of four L-deoxynucleosides and the L-oligonucleotide-ethidium bromide interactions. The L-deoxyribose synthon 9 was synthesized from L-arabinose with an over all yield of 28.5% via the Barton-McCo...

The biosynthesis of ribose and deoxyribose in Escherichia coli involves both the oxidative pathway through 6-phosphogluconate and the nonoxidative pathway through the transketolase and transaldolase sequence (Lanning and Cohen, 1954; Bernstein, 1956; Bagatell, Wright, and Sable, 1959). The proportions of the oxidative and nonoxidative pathways depend on the nature of the principal carbon source...

In the presence of transition metal ions and peroxides, polyphenols, well-known dietary antioxidants, can act as pro-oxidants. We investigated the effect of 13 polyphenols and their metabolites on oxidative degradation of deoxyribose by an •OH generating Fenton system (Fe2+-ethylenediaminetetraacetic acid (EDTA)-H₂O₂). The relationship between phenolics pro-oxidant/anti-oxidant effects and thei...

An ab initio method is used in a two state model to calculate consistent relative enthalpies and free energies for the stacking of nucleic acid bases in deoxyribose dinucleotides and the Watson-Crick hydrogen bonding interactions between mononucleotides when uncharged and singly charged. Favorable free energy changes are determined for the formation of dimers between mononucleotides by Watson-C...

The family of proteins that are homologous to RecA protein of Escherichia coli is essential to homologous genetic recombination in various organisms including viruses, bacteria, lower eukaryotes, and mammals. In the presence of ATP (or ATPgammaS), these proteins form helical filaments containing single-stranded DNA at the center. The single-stranded DNA bound to RecA protein is extended 1.5 tim...

Investigation of in vitro hydroxyl radical scavenging (antioxidant) effect 4-methoxychalcone (1a) and its cyclic analogues (2a-4a), as well as their hydroxyl substituted counterparts (1b-4b) was performed by means of the Fenton-reaction initiated deoxyribose degradation assay in short term (10 minute) and long term (240 minute) experiments. The kinetic deoxyribose method provides possibility to...

Maillard reaction products were prepared by heating xylose and lysine at pH 9.0 and 100°C for 3 h, and then fractionated by ethyl ether and ethanol into acidic, neutral and basic low-molecular-weight, ethanol-soluble and ethanol-insoluble fractions. The ethanol-soluble and -insoluble fractions were the major fractions of the xylose-lysine Maillard reaction products (XL MRPs), contributing 79.5%...