RESUMEN
Small molecule inhibitors have a powerful blocking action on viral polymerases. The bioavailability of the inhibitor, nevertheless, often raise a significant selectivity constraint and may substantially limit the efficacy of therapy. Phosphonoacetic acid has long been known to possess a restricted potential to block DNA biosynthesis. In order to achieve a better affinity, this compound has been linked with natural nucleotide at different positions. The structural context of the resulted conjugates has been found to be crucial for the acquisition by DNA polymerases. We show that nucleobase-conjugated phosphonoacetic acid is being accepted, but this alters the processivity of DNA polymerases. The data presented here not only provide a mechanistic rationale for a switch in the mode of DNA synthesis, but also highlight the nucleobase-targeted nucleotide functionalization as a route for enhancing the specificity of small molecule inhibitors.
Asunto(s)
ADN Polimerasa Dirigida por ADN/metabolismo , Inhibidores Enzimáticos/farmacología , Nucleótidos/farmacología , Ácido Fosfonoacético/farmacología , Inhibidores Enzimáticos/síntesis química , Inhibidores Enzimáticos/química , VIH-1/enzimología , Estructura Molecular , Virus de la Leucemia Murina de Moloney/enzimología , Nucleótidos/química , Ácido Fosfonoacético/síntesis química , Ácido Fosfonoacético/químicaRESUMEN
The synthesis and characterization of novel acyclic and cyclic pyridone-based nucleosides and nucleotides is described. In total, seven nucleosides and four nucleotides were synthesized. None of the tested nucleosides showed inhibitory properties against Klenow exo- polymerase and M.MuLV and HIV-1 reverse transcriptases. The nucleotides containing 4-chloro- and 4-bromo-2-pyridone as a nucleobase were accepted by the Klenow fragment, but at the expense of fidelity and extension efficiency.
