Skip to main content

Thank you for visiting nature.com. You are using a browser version with limited support for CSS. To obtain the best experience, we recommend you use a more up to date browser (or turn off compatibility mode in Internet Explorer). In the meantime, to ensure continued support, we are displaying the site without styles and JavaScript.

  • Article
  • Published:

Mechanism of regulation and neutralization of the AtaR–AtaT toxin–antitoxin system

Abstract

GCN5-related N-acetyl-transferase (GNAT)-like enzymes from toxin–antitoxin modules are strong inhibitors of protein synthesis. Here, we present the bases of the regulatory mechanisms of ataRT, a model GNAT-toxin–antitoxin module, from toxin synthesis to its action as a transcriptional de-repressor. We show the antitoxin (AtaR) traps the toxin (AtaT) in a pre-catalytic monomeric state and precludes the effective binding of ac-CoA and its target Met-transfer RNAfMet. In the repressor complex, AtaR intrinsically disordered region interacts with AtaT at two different sites, folding into different structures, that are involved in two separate functional roles, toxin neutralization and placing the DNA-binding domains of AtaR in a binding-compatible orientation. Our data suggests AtaR neutralizes AtaT as a monomer, right after its synthesis and only the toxin–antitoxin complex formed in this way is an active repressor. Once activated by dimerization, later neutralization of the toxin results in a toxin–antitoxin complex that is not able to repress transcription.

This is a preview of subscription content, access via your institution

Access options

Buy this article

Prices may be subject to local taxes which are calculated during checkout

Fig. 1: Structure and Met-tRNAfMet binding site mapping of AtaT.
Fig. 2: Structure of free AtaR and mapping of the toxin neutralization region.
Fig. 3: Mechanism of recognition and neutralization of AtaT by AtaR.
Fig. 4: Transcription repression by AtaR and AtaR–AtaT.
Fig. 5: Structure of AtaT–AtaR2–Opr22–AtaR2–AtaT.
Fig. 6: Cartoon representation of the molecular model for the mechanism of regulation of the ataRT operon.

Similar content being viewed by others

Data availability

All the structures have been deposited in the PDB database with the following accession numbers: 6GTO, 6GTQ, 6GTP, 6GTR and 6GTS. All data needed to evaluate the conclusions in the paper are present in the paper and/or the Methods. Additional data related to this paper may be requested from the authors.

References

  1. Dyda, F., Klein, D. C. & Hickman, A. B. GCN5-related N-acetyltransferases: a structural overview. Annu. Rev. Biophys. Biomol. Struct. 29, 81–103 (2000).

    Article  CAS  Google Scholar 

  2. Jurėnas, D., Garcia-Pino, A. & Van Melderen, L. Novel toxins from type II toxin–antitoxin systems with acetyltransferase activity. Plasmid 93, 30–35 (2017).

    Article  Google Scholar 

  3. Harms, A., Brodersen, D. E., Mitarai, N. & Gerdes, K. Toxins, targets, and triggers: an overview of toxin–antitoxin biology. Mol. Cell 70, 768–784 (2018).

    Article  CAS  Google Scholar 

  4. Cheverton, A. M. et al. A Salmonella toxin promotes persister formation through acetylation of tRNA. Mol. Cell 63, 86–96 (2016).

    Article  CAS  Google Scholar 

  5. Helaine, S. et al. Internalization of Salmonella by macrophages induces formation of nonreplicating persisters. Science 343, 204–208 (2014).

    Article  CAS  Google Scholar 

  6. Goormaghtigh, F. et al. Reassessing the role of type II toxin–antitoxin systems in formation of Escherichia coli type II persister cells. mBio 9, e00640e-18 (2018).

    Article  Google Scholar 

  7. Jurėnas, D. et al. AtaT blocks translation initiation by N-acetylation of the initiator tRNAfMet. Nat. Chem. Biol. 13, 640–646 (2017).

    Article  Google Scholar 

  8. Rycroft, J. A. et al. Activity of acetyltransferase toxins involved in Salmonella persister formation during macrophage infection. Nat. Commun. 9, 1993 (2018).

    Article  Google Scholar 

  9. Wilcox, B. et al. Escherichia coli ItaT is a type II toxin that inhibits translation by acetylating isoleucyl-tRNAIle. Nucleic Acids Res. 46, 7873–7885 (2018).

    Article  Google Scholar 

  10. Jurėnas, D., Van Melderen, L. & Garcia-Pino, A. Crystallization and X-ray analysis of all of the players in the autoregulation of the ataRT toxin–antitoxin system. Acta Crystallogr. F Struct. Biol. Commun. 74, 391–401 (2018).

    Article  Google Scholar 

  11. Loris, R. & Garcia-Pino, A. Disorder- and dynamics-based regulatory mechanisms in toxin–antitoxin modules. Chem. Rev. 114, 6933–6947 (2014).

    Article  CAS  Google Scholar 

  12. Buts, L., Lah, J., Dao-Thi, M. H., Wyns, L. & Loris, R. Toxin–antitoxin modules as bacterial metabolic stress managers. Trends. Biochem. Sci. 30, 672–679 (2005).

    Article  CAS  Google Scholar 

  13. Hayes, F. & Van Melderen, L. Toxins–antitoxins: diversity, evolution and function. Crit. Rev. Biochem. Mol. Biol. 46, 386–408 (2011).

    Article  CAS  Google Scholar 

  14. Garcia-Pino, A. et al. An intrinsically disordered entropic switch determines allostery in Phd-Doc regulation. Nat. Chem. Biol. 12, 490–496 (2016).

    Article  CAS  Google Scholar 

  15. Qian, H. et al. Identification and characterization of acetyltransferase-type toxin–antitoxin locus in Klebsiella pneumoniae. Mol. Microbiol. 108, 336–349 (2018).

    Article  CAS  Google Scholar 

  16. Takamura, Y. & Nomura, G. Changes in the intracellular concentration of acetyl-CoA and malonyl-CoA in relation to the carbon and energy metabolism of Escherichia coli K12. J. Gen. Microbiol. 134, 2249–2253 (1988).

    CAS  PubMed  Google Scholar 

  17. Vallari, D. S. & Jackowski, S. Biosynthesis and degradation both contribute to the regulation of coenzyme A content in. Escherichia coli. J. Bacteriol. 170, 3961–3966 (1988).

    CAS  PubMed  Google Scholar 

  18. Kamada, K., Hanaoka, F. & Burley, S. K. Crystal structure of the MazE/MazF complex: molecular bases of antidote–toxin recognition. Mol. Cell 11, 875–884 (2003).

    Article  CAS  Google Scholar 

  19. Kamada, K. & Hanaoka, F. Conformational change in the catalytic site of the ribonuclease YoeB toxin by YefM antitoxin. Mol. Cell 19, 497–509 (2005).

    Article  CAS  Google Scholar 

  20. Hadži, S. et al. Ribosome-dependent Vibrio cholerae mRNAse HigB2 is regulated by a β-strand sliding mechanism. Nucleic Acids Res. 45, 4972–4983 (2017).

    Article  Google Scholar 

  21. Garcia-Pino, A. et al. Doc of prophage P1 is inhibited by its antitoxin partner Phd through fold complementation. J. Biol. Chem. 283, 30821–30827 (2008).

    Article  CAS  Google Scholar 

  22. Engel, P. et al. Adenylylation control by intra- or intermolecular active-site obstruction in Fic proteins. Nature 482, 107–110 (2012).

    Article  CAS  Google Scholar 

  23. De Jonge, N. et al. Rejuvenation of CcdB-poisoned gyrase by an intrinsically disordered protein domain. Mol. Cell 35, 154–163 (2009).

    Article  Google Scholar 

  24. Dao-Thi, M. H. et al. Intricate interactions within the ccd plasmid addiction system. J. Biol. Chem. 277, 3733–3742 (2002).

    Article  CAS  Google Scholar 

  25. Madl, T. et al. Structural basis for nucleic acid and toxin recognition of the bacterial antitoxin CcdA. J. Mol. Biol. 364, 170–185 (2006).

    Article  CAS  Google Scholar 

  26. Schreiter, E. R. & Drennan, C. L. Ribbon-helix-helix transcription factors: variations on a theme. Nat. Rev. Microbiol. 5, 710–720 (2007).

    Article  CAS  Google Scholar 

  27. Ball, L. J., Kühne, R., Schneider-Mergener, J. & Oschkinat, H. Recognition of proline-rich motifs by protein-protein-interaction domains. Angew. Chem. Int. Edn Engl. 44, 2852–2869 (2005).

    Article  CAS  Google Scholar 

  28. Ceregido, M. A. et al. Multimeric and differential binding of CIN85/CD2AP with two atypical proline-rich sequences from CD2 and Cbl-b*. FEBS. J. 280, 3399–3415 (2013).

    Article  CAS  Google Scholar 

  29. Page, R. & Peti, W. Toxin–antitoxin systems in bacterial growth arrest and persistence. Nat. Chem. Biol. 12, 208–214 (2016).

    Article  CAS  Google Scholar 

  30. Garcia-Pino, A. et al. Allostery and intrinsic disorder mediate transcription regulation by conditional cooperativity. Cell 142, 101–111 (2010).

    Article  CAS  Google Scholar 

  31. Raumann, B. E., Rould, M. A., Pabo, C. O. & Sauer, R. T. DNA recognition by β-sheets in the Arc repressor-operator crystal structure. Nature 367, 754–757 (1994).

    Article  CAS  Google Scholar 

  32. Schneidman-Duhovny, D., Hammel, M., Tainer, J. A. & Sali, A. FoXS, FoXSDock and MultiFoXS: single-state and multi-state structural modeling of proteins and their complexes based on SAXS profiles. Nucleic Acids Res. 44, W424–W429 (2016).

    Article  CAS  Google Scholar 

  33. Andersen, J. B. et al. New unstable variants of green fluorescent protein for studies of transient gene expression in bacteria. Appl. Environ. Microbiol. 64, 2240–2246 (1998).

    CAS  PubMed  PubMed Central  Google Scholar 

  34. Chatterjee, A. N. & Park, J. T. Biosynthesis of cell wall mucopeptide by a particulate fraction from Staphylococcus aureus. Proc. Natl Acad. Sci. USA 51, 9–16 (1964).

    Article  CAS  Google Scholar 

  35. Petit, J. F., Strominger, J. L. & Söll, D. Biosynthesis of the peptidoglycan of bacterial cell walls. VII. Incorporation of serine and glycine into interpeptide bridges in Staphylococcus epidermidis. J. Biol. Chem. 243, 757–767 (1968).

    CAS  PubMed  Google Scholar 

  36. Hebecker, S. et al. Structures of two bacterial resistance factors mediating tRNA-dependent aminoacylation of phosphatidylglycerol with lysine or alanine. Proc. Natl Acad. Sci. USA 112, 10691–10696 (2015)

    Article  CAS  Google Scholar 

  37. Tasaki, T., Sriram, S. M., Park, K. S. & Kwon, Y. T. The N-end rule pathway. Annu. Rev. Biochem. 81, 261–289 (2012).

    Article  CAS  Google Scholar 

  38. Castro-Roa, D. et al. The Fic protein Doc uses an inverted substrate to phosphorylate and inactivate EF-Tu. Nat. Chem. Biol. 9, 811–817 (2013).

    Article  CAS  Google Scholar 

  39. Garcia-Pino, A., Zenkin, N. & Loris, R. The many faces of Fic: structural and functional aspects of Fic enzymes. Trends. Biochem. Sci. 39, 121–129 (2014).

    Article  CAS  Google Scholar 

  40. Marimon, O. et al. An oxygen-sensitive toxin–antitoxin system. Nat. Commun. 7, 13634 (2016).

    Article  CAS  Google Scholar 

  41. Goeders, N. & Van Melderen, L. Toxin–antitoxin systems as multilevel interaction systems. Toxins 6, 304–324 (2014).

    Article  CAS  Google Scholar 

  42. Bendtsen, K. L. et al. Toxin inhibition in C. crescentus VapBC1 is mediated by a flexible pseudo-palindromic protein motif and modulated by DNA binding. Nucleic Acids Res. 45, 2875–2886 (2017).

    CAS  PubMed  Google Scholar 

  43. Kabsch, W. Xds. Acta Crystallogr. D. Biol. Crystallogr. 66, 125–132 (2010).

    Article  CAS  Google Scholar 

  44. Evans, P. Scaling and assessment of data quality. Acta Crystallogr. D. Biol. Crystallogr. 62, 72–82 (2006).

    Article  Google Scholar 

  45. Afonine, P. V. et al. Towards automated crystallographic structure refinement with phenix.refine. Acta Crystallogr. D. Biol. Crystallogr. 68, 352–367 (2012).

    Article  CAS  Google Scholar 

  46. Sheldrick, G. M. Experimental phasing with SHELXC/D/E: combining chain tracing with density modification. Acta Crystallogr. D. Biol. Crystallogr. 66, 479–485 (2010).

    Article  CAS  Google Scholar 

  47. Garcia-Pino, A., Buts, L., Wyns, L. & Loris, R. Interplay between metal binding and cis/trans isomerization in legume lectins: structural and thermodynamic study of P. angolensis lectin. J. Mol. Biol. 361, 153–167 (2006).

    Article  CAS  Google Scholar 

Download references

Acknowledgements

We acknowledge the use of the synchrotron-radiation facility at the Soleil synchrotron Gif-sur-Yvette, France, under proposals 20150717, 20160750 and 20170756; Diamond Light Source, Didcot, UK, under proposal MX9426; and access support from the European Community’s Seventh Framework Program (FP7/2007–2013) under BioStruct-X (projects 1673 and 6131). We also thank the staff from Swing, PROXIMA-1 and PROXIMA-2A beamlines at Soleil for assistance with data collection. F. Goormaghtigh and A. Talavera are thanked for technical assistance with the Flow Cytometry and SEC-multiangle light scattering measurements. This work was supported by grants from the Fonds National de Recherche Scientifique nos. FNRS-MIS F.4505.16, FNRS-EQP U.N043.17F, FRFS-WELBIO CR-2017S-03 and FNRS-PDR T.0066.18 to A.G.-P. and FNRS-PDR T.0147.15F and FNRS-CDR J.0061.16F to L.V.M.; the Program ‘Actions de Recherche Concertée’ 2016–2021 from the ULB, the Fonds d’Encouragement à la Recherche (FER) ULB to A.G.-P.; and the Fonds Jean Brachet and the Fondation Van Buuren to A.G.-P. and L.V.M. D.J. was supported by a PhD grant from the Fonds National de Recherche Scientifique FNRS-ASPIRANT.

Author information

Authors and Affiliations

Authors

Contributions

D.J., L.V.M. and A.G.-P. designed research. D.J. performed the research. D.J. and A.G.-P. analyzed the data. D.J., L.V.M. and A.G.-P. wrote the paper.

Corresponding author

Correspondence to Abel Garcia-Pino.

Ethics declarations

Competing interests

The authors declare no competing interests.

Additional information

Publisher’s note: Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

Supplementary information

Supplementary Text and Figures

Supplementary Tables 1–5, Supplementary Figures 1–9

Reporting Summary

Rights and permissions

Reprints and permissions

About this article

Check for updates. Verify currency and authenticity via CrossMark

Cite this article

Jurėnas, D., Van Melderen, L. & Garcia-Pino, A. Mechanism of regulation and neutralization of the AtaR–AtaT toxin–antitoxin system. Nat Chem Biol 15, 285–294 (2019). https://doi.org/10.1038/s41589-018-0216-z

Download citation

  • Received:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1038/s41589-018-0216-z

This article is cited by

Search

Quick links

Nature Briefing

Sign up for the Nature Briefing newsletter — what matters in science, free to your inbox daily.

Get the most important science stories of the day, free in your inbox. Sign up for Nature Briefing