Chemical modification of p5’A2’(p5’A2’),p5’A by a periodate oxidation/Schiff base formation/borohydride reduction cycle gave a series of 2-5A analogues in which the ribose of the 2’-terminal nucleotide was transformed to an N-substituted morpholine (azahexapyranose). 2’,5’-Oligoriboadenylate 5’-monophosphates bearing this modification were 5-10 times more potent as antagonists of the action of ...

The solution complexes of ethidium bromide with nine different deoxydinucleotides and the four self-complementary ribodinucleoside monophosphates as well as mixtures of complementary and noncomplementary deoxydinucleotides were studied as models for the binding of the drug to DNA and RNA. Ethidium bromide forms the strongest complexes with pdCdG and CpG and shows a definite preference for inter...

We have demonstrated that acylphosphatase possesses ATP-diphosphohydrolase (apyrase-like) activity. In fact, acylphosphatase first catalyses the hydrolysis of the gamma-phosphate group of nucleoside triphosphates, and then attacks the beta-phosphate group of the initially produced nucleoside diphosphates, generating nucleoside monophosphates. In contrast, it binds nucleoside monophosphates but ...

Cytosolic 5'-nucleotidase II (cN-II) regulates the intracellular nucleotide pools within the cell by catalyzing the dephosphorylation of 6-hydroxypurine nucleoside 5'-monophosphates. Beside this physiological function, high level of cN-II expression is correlated with abnormal patient outcome when treated with cytotoxic nucleoside analogues. To identify its specific role in the resistance pheno...

The interaction of Magnesium hydrate at the phosphate oxygen atom of the pyrimidine nucleotides (CMP,UMP,dTMP) were studied at the Hartree-Fock level Theory. We used LANL2DZ basis set for Mg and 6-31g* basis set for atoms.The basis set superposition error (BSSE) begins to converge for used Method/basis set. The gauge-invariant atomic orbital (GIAO) method and the continuous-set-of-gauge-transfo...

5’-Phosphodiesterase (5’-PDE) is an enzyme that hydrolyses RNA to form 5’-inosine monophosphate (5’-IMP) and 5’-guanosine monophosphate (5’-GMP), which function as flavour enhancers. Selection of the best producer of 5’-PDE was made by determining the activity of the enzyme in six seeds that have been germinated, namely mung bean (Vigna radiate), soybean (Glycine max), adzuki/red bean (Vigna an...

The nonenzymatic replication of primordial RNA is thought to have been a critical step in the origin of life. However, despite decades of effort, the poor rate and fidelity of model template copying reactions have thus far prevented an experimental demonstration of nonenzymatic RNA replication. The overall rate and fidelity of template copying depend, in part, on the affinity of free ribonucleo...

Template-directed polymerization of RNA in the absence of enzymes is the basis for an information transfer in the 'RNA-world' hypothesis and in novel nucleic acid based technology. Previous investigations established that only cytidine rich strands are efficient templates in bulk aqueous solutions while a few specific sequences completely block the extension of hybridized primers. We show that ...