Identification of elongation factor G as the conserved cellular target of argyrin B

Beat Nyfeler; Dominic Hoepfner; Deborah Palestrant; Christina A Kirby; Lewis Whitehead; Robert Yu; Gejing Deng; Ruth E Caughlan; Angela L Woods; Adriana K Jones; S Whitney Barnes; John R Walker; Swann Gaulis; Ervan Hauy; Saskia M Brachmann; Philipp Krastel; Christian Studer; Ralph Riedl; David Estoppey; Thomas Aust; N Rao Movva; Zuncai Wang; Michael Salcius; Gregory A Michaud; Gregory McAllister; Leon O Murphy; John A Tallarico; Christopher J Wilson; Charles R Dean

doi:10.1371/journal.pone.0042657

Identification of elongation factor G as the conserved cellular target of argyrin B

PLoS One. 2012;7(9):e42657. doi: 10.1371/journal.pone.0042657. Epub 2012 Sep 10.

Affiliation

¹ Developmental and Molecular Pathways, Novartis Institutes for BioMedical Research, Cambridge, Massachussetts, United States of America.

Abstract

Argyrins, produced by myxobacteria and actinomycetes, are cyclic octapeptides with antibacterial and antitumor activity. Here, we identify elongation factor G (EF-G) as the cellular target of argyrin B in bacteria, via resistant mutant selection and whole genome sequencing, biophysical binding studies and crystallography. Argyrin B binds a novel allosteric pocket in EF-G, distinct from the known EF-G inhibitor antibiotic fusidic acid, revealing a new mode of protein synthesis inhibition. In eukaryotic cells, argyrin B was found to target mitochondrial elongation factor G1 (EF-G1), the closest homologue of bacterial EF-G. By blocking mitochondrial translation, argyrin B depletes electron transport components and inhibits the growth of yeast and tumor cells. Further supporting direct inhibition of EF-G1, expression of an argyrin B-binding deficient EF-G1 L693Q variant partially rescued argyrin B-sensitivity in tumor cells. In summary, we show that argyrin B is an antibacterial and cytotoxic agent that inhibits the evolutionarily conserved target EF-G, blocking protein synthesis in bacteria and mitochondrial translation in yeast and mammalian cells.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Allosteric Site
Amino Acid Sequence
Animals
Burkholderia / drug effects
Cell Line, Tumor
Conserved Sequence
Crystallography, X-Ray
Humans
Mammals
Microbial Sensitivity Tests
Mitochondrial Proteins / metabolism
Molecular Sequence Data
Mutant Proteins / chemistry
Mutant Proteins / metabolism
Oligopeptides / chemistry
Oligopeptides / metabolism*
Oligopeptides / pharmacology
Peptide Elongation Factor G / antagonists & inhibitors
Peptide Elongation Factor G / chemistry
Peptide Elongation Factor G / metabolism*
Protein Binding / drug effects
Pseudomonas aeruginosa / drug effects
Saccharomyces cerevisiae / metabolism
Sequence Homology, Amino Acid

Substances

Mitochondrial Proteins
Mutant Proteins
Oligopeptides
Peptide Elongation Factor G
argyrin B

Associated data

PDB/4FN5

Grants and funding

Funding of this research was provided solely within the Novartis organization as per standard research activities. The funders (NIBR) had no role in study design, data collection and analysis, or preparation of the manuscript. The manuscript was assessed by the Novartis legal department as well as senior mangement in chemistry and biolgy (Infectious diseases and Global) to ascertain that release of this manuscript did not contravene Novartis policy regarding release of proprietary information, but this was limited only to approval for release of the material and was not related to the results or interpretations/conclusions contained in the manuscript.