Plitidepsin has potent preclinical efficacy against SARS-CoV-2 by targeting the host protein eEF1A

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) viral proteins interact with the eukaryotic translation machinery, and inhibitors of translation have potent antiviral effects. We found that the drug plitidepsin (aplidin), which has limited clinical approval, possesses antiviral activity (90% inhibitory concentration = 0.88 nM) that is more potent than remdesivir against SARS-CoV-2 in vitro by a factor of 27.5, with limited toxicity in cell culture. Through the use of a drug-resistant mutant, we show that the antiviral activity of plitidepsin against SARS-CoV-2 is mediated through inhibition of the known target eEF1A (eukaryotic translation elongation factor 1A). We demonstrate the in vivo efficacy of plitidepsin treatment in two mouse models of SARS-CoV-2 infection with a reduction of viral replication in the lungs by two orders of magnitude using prophylactic treatment. Our results indicate that plitidepsin is a promising therapeutic candidate for COVID-19.

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Overexpression of Translation Elongation Factor 1A Affects the Organization and Function of the Actin Cytoskeleton in Yeast

Genetics ◽

10.1093/genetics/157.4.1425 ◽

2001 ◽

Vol 157 (4) ◽

pp. 1425-1436

Author(s):

Raj Munshi ◽

Kimberly A Kandl ◽

Anne Carr-Schmid ◽

Johanna L Whitacre ◽

Alison E M Adams ◽

...

Keyword(s):

Protein Synthesis ◽

Elongation Factor ◽

Nucleotide Exchange ◽

Translation Elongation Factor ◽

Translation Elongation ◽

Guanine Nucleotide Exchange ◽

Nucleotide Exchange Factor ◽

And Function

Abstract The translation elongation factor 1 complex (eEF1) plays a central role in protein synthesis, delivering aminoacyl-tRNAs to the elongating ribosome. The eEF1A subunit, a classic G-protein, also performs roles aside from protein synthesis. The overexpression of either eEF1A or eEF1Bα, the catalytic subunit of the guanine nucleotide exchange factor, in Saccharomyces cerevisiae results in effects on cell growth. Here we demonstrate that overexpression of either factor does not affect the levels of the other subunit or the rate or accuracy of protein synthesis. Instead, the major effects in vivo appear to be at the level of cell morphology and budding. eEF1A overexpression results in dosage-dependent reduced budding and altered actin distribution and cellular morphology. In addition, the effects of excess eEF1A in actin mutant strains show synthetic growth defects, establishing a genetic connection between the two proteins. As the ability of eEF1A to bind and bundle actin is conserved in yeast, these results link the established ability of eEF1A to bind and bundle actin in vitro with nontranslational roles for the protein in vivo.

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Structural basis for EarP-mediated arginine glycosylation of translation elongation factor EF-P

10.1101/116038 ◽

2017 ◽

Author(s):

Ralph Krafczyk ◽

Jakub Macošek ◽

Daniel Gast ◽

Swetlana Wunder ◽

Pravin Kumar Ankush Jagtap ◽

...

Keyword(s):

Elongation Factor ◽

Structural Data ◽

Enzyme Characterization ◽

Structural Basis ◽

Translation Elongation Factor ◽

Translation Elongation ◽

Enzymatic Mechanism ◽

Bacterial Translation

ABSTRACTGlycosylation is a universal strategy to post-translationally modify proteins. The recently discovered arginine rhamnosylation activates the polyproline specific bacterial translation elongation factor EF-P. EF-P is rhamnosylated on arginine 32 by the glycosyltransferase EarP. However, the enzymatic mechanism remains elusive. In the present study, we solved the crystal structure of EarP from Pseudomonas putida. The enzyme is composed of two opposing domains with Rossmann-folds, thus constituting a GT-B glycosyltransferase. While TDP-rhamnose is located within a highly conserved pocket of the C-domain, EarP recognizes the EF-P via its KOW-like N-domain. Based on our structural data combined with an in vitro /in vivo enzyme characterization, we propose a mechanism of inverting arginine glycosylation. As EarP is essential for pathogenicity in P. aeruginosa our study provides the basis for targeted inhibitor design.

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