galidesivir and triphosphoric-acid

Millions of people are infected by the dengue and Zika viruses each year, resulting in significant morbidity and mortality. Galidesivir is an adenosine nucleoside analog that can attenuate flavivirus replication in cell-based assays and animal models of infection. Galidesivir is converted to the triphosphorylated form by host kinases and subsequently incorporated into viral RNA by viral RNA polymerases. This has been proposed to lead to the delayed termination of RNA synthesis. Here, we report direct in vitro testing of the effects of Galidesivir triphosphate on dengue-2 and Zika virus polymerase activity. Galidesivir triphosphate was chemically synthesized, and inhibition of RNA synthesis followed using a dinucleotide-primed assay with a homopolymeric poly(U) template. Galidesivir triphosphate was equipotent against dengue-2 and Zika polymerases, with IC

Topics: Adenosine; Animals; Antiviral Agents; Dengue; Nucleotidyltransferases; RNA, Viral; Zika Virus; Zika Virus Infection

The C-P lyase complex in bacteria catalyzes the transformation of phosphonates to orthophosphate under conditions of phosphate starvation. The first committed step in the C-P lyase-catalyzed reaction is the displacement of adenine from MgATP by phosphonate substrates, yielding ribose-1-phosphonate-5-triphosphate. In the C-P lyase complex, this reaction is catalyzed by the nucleosidase PhnI and modulated by the addition of PhnG, PhnH, and PhnL. Here we describe the synthesis of Immucillin-A triphosphate, a mimic of the transition state structure for the nucleosidase reaction catalyzed by PhnI. This compound inhibits PhnI with a dissociation constant of 20 nM at pH 7.5.

Topics: Adenine; Adenosine; Adenosine Triphosphate; Catalysis; Escherichia coli; Escherichia coli Proteins; Lyases; Magnesium; Models, Chemical; Organophosphonates; Pentosephosphates; Polyphosphates; Pyrrolidines