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:

Identification of a radical SAM enzyme involved in the synthesis of archaeosine

Abstract

Archaeosine (G+), 7-formamidino-7-deazaguanosine, is an archaea-specific modified nucleoside found at the 15th position of tRNAs. In Euryarchaeota, 7-cyano-7-deazaguanine (preQ0)-containing tRNA (q0N-tRNA), synthesized by archaeal tRNA-guanine transglycosylase (ArcTGT), has been believed to be converted to G+-containing tRNA (G+-tRNA) by the paralog of ArcTGT, ArcS. However, we found that several euryarchaeal ArcSs have lysine transfer activity to q0N-tRNA to form q0kN-tRNA, which has a preQ0 lysine adduct as a base. Through comparative genomics and biochemical experiments, we found that ArcS forms a robust complex with a radical S-adenosylmethionine (SAM) enzyme named RaSEA. The ArcS–RaSEA complex anaerobically converted q0N-tRNA to G+-tRNA in the presence of SAM and lysine via q0kN-tRNA. We propose that ArcS and RaSEA should be considered an archaeosine synthase α-subunit (lysine transferase) and β-subunit (q0kN-tRNA lyase), respectively.

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: Lysine transfer activity of T. acidophilum and T. kodakarensis ArcSs.
Fig. 2: Chemical structure of preQ0-nucleoside lysine adduct.
Fig. 3: Physical interaction between TkRaSEA and TkArcS or TaArcS in E. coli.
Fig. 4: In vitro G+15-tRNA synthsis by ArcS–RaSEA complexes.
Fig. 5: G+15-tRNA synthesis in E. coli cells producing MaArcTGT and the MaArcS–MaRaSEA complex.
Fig. 6: Archaeosine biosynthesis pathway.

Similar content being viewed by others

Data availability

The data supporting findings in this study are available from the corresponding author for reasonable requests.

References

  1. Boccaletto, P. et al. MODOMICS: a database of RNA modification pathways. 2017 update. Nucleic Acids Res. 46, D303–D307 (2018).

    CAS  PubMed  Google Scholar 

  2. Hori, H. et al. Transfer RNA modification enzymes from thermophiles and their modified nucleosides in tRNA. Microorganisms 6, E110 (2018).

    PubMed  Google Scholar 

  3. Kilpatrick, M. W. & Walker, R. T. The nucleotide sequence of the tRNAM Met from the archaebacterium Thermoplasma acidophilum. Nucleic Acids Res. 9, 4387–4390 (1981).

    CAS  PubMed  PubMed Central  Google Scholar 

  4. Gupta, R. Halobacterium volcanii tRNAs. Identification of 41 tRNAs covering all amino acids, and the sequences of 33 class I tRNAs. J. Biol. Chem. 259, 9461–9471 (1984).

    CAS  PubMed  Google Scholar 

  5. Gregson, J. M. et al. Structure of the archaeal transfer RNA nucleoside G*-15 (2-amino-4,7-dihydro-4-oxo-7-β-d-ribofuranosyl-1H-pyrrolo[2,3-d]pyrimidine-5-carboximidamide (archaeosine)). J. Biol. Chem. 268, 10076–10086 (1993).

    CAS  PubMed  Google Scholar 

  6. Noon, K. R. et al. Influence of temperature on tRNA modification in archaea: Methanococcoides burtonii (optimum growth temperature [T opt], 23 °C) and Stetteria hydrogenophila (T opt, 95 °C). J. Bacteriol. 185, 5483–5490 (2003).

    CAS  PubMed  PubMed Central  Google Scholar 

  7. Tomikawa, C. et al. Distinct tRNA modifications in the thermo-acidophilic archaeon, Thermoplasma acidophilum. FEBS Lett. 587, 3575–3580 (2013).

    CAS  PubMed  Google Scholar 

  8. Oliva, R., Tramontano, A. & Cavallo, L. Mg2+ binding and archaeosine modification stabilize the G15 C48 Levitt base pair in tRNAs. RNA 13, 1427–1436 (2007).

    CAS  PubMed  PubMed Central  Google Scholar 

  9. Watanabe, M. et al. Biosynthesis of archaeosine, a novel derivative of 7-deazaguanosine specific to archaeal tRNA, proceeds via a pathway involving base replacement on the tRNA polynucleotide chain. J. Biol. Chem. 272, 20146–20151 (1997).

    CAS  PubMed  Google Scholar 

  10. Bai, Y., Fox, D. T., Lacy, J. A., Van Lanen, S. G. & Iwata-Reuyl, D. Hypermodification of tRNA in thermophilic archaea. Cloning, overexpression, and characterization of tRNA-guanine transglycosylase from Methanococcus jannaschii. J. Biol. Chem. 275, 28731–28738 (2000).

    CAS  PubMed  Google Scholar 

  11. Watanabe, M., Nameki, N., Matsuo-Takasaki, M., Nishimura, S. & Okada, N. tRNA recognition of tRNA-guanine transglycosylase from a hyperthermophilic archaeon, Pyrococcus horikoshii. J. Biol. Chem. 276, 2387–2394 (2001).

    CAS  PubMed  Google Scholar 

  12. Ishitani, R. et al. Crystal structure of archaeosine tRNA-guanine transglycosylase. J. Mol. Biol. 318, 665–677 (2002).

    CAS  PubMed  Google Scholar 

  13. Ishitani, R. et al. Alternative tertiary structure of tRNA for recognition by a posttranscriptional modification enzyme. Cell 113, 383–394 (2003).

    CAS  PubMed  Google Scholar 

  14. Sabina, J. & Söll, D. The RNA-binding PUA domain of archaeal tRNA-guanine transglycosylase is not required for archaeosine formation. J. Biol. Chem. 281, 6993–7001 (2006).

    CAS  PubMed  Google Scholar 

  15. Phillips, G. et al. Discovery and characterization of an amidinotransferase involved in the modification of archaeal tRNA. J. Biol. Chem. 285, 12706–12713 (2010).

    CAS  PubMed  PubMed Central  Google Scholar 

  16. Phillips, G. et al. Diversity of archaeosine synthesis in Crenarchaeota. ACS Chem. Biol. 7, 300–305 (2012).

    CAS  PubMed  Google Scholar 

  17. Kawamura, T. et al. Multisite-specific archaeosine tRNA-guanine transglycosylase (ArcTGT) from Thermoplasma acidophilum, a thermo-acidophilic archaeon. Nucleic Acids Res. 44, 1894–1908 (2016).

    PubMed  Google Scholar 

  18. Mei, X. et al. Crystal structure of the archaeosine synthase QueF-like—insights into amidino transfer and tRNA recognition by the tunnel fold. Proteins 85, 103–116 (2017).

    CAS  PubMed  Google Scholar 

  19. Bon Ramos, A., Bao, L., Turner, B., de Crécy-Lagard, V. & Iwata-Reuyl, D. QueF-like, a non-homologous archaeosine synthase from the Crenarchaeota. Biomolecules 7, E36 (2017).

    PubMed  Google Scholar 

  20. Wakita, K. et al. Higher-order structure of bovine mitochondrial tRNAPhe lacking the ‘conserved’ GG and TΨCG sequences as inferred by enzymatic and chemical probing. Nucleic Acids Res. 22, 347–353 (1994).

    CAS  PubMed  PubMed Central  Google Scholar 

  21. Hasegawa, T. & Yokogawa, T. Escherichia coli proline tRNA: structure and recognition sites for prolyl-tRNA synthetase. Nucleic Acids Symp. Ser. 44, 7–8 (2000).

    Google Scholar 

  22. Awai, T. et al. Aquifex aeolicus tRNA (N 2,N 2-guanine)-dimethyltransferase (Trm1) catalyzes transfer of methyl groups not only to guanine 26 but also to guanine 27 in tRNA. J. Biol. Chem. 284, 20467–20478 (2009).

    CAS  PubMed  PubMed Central  Google Scholar 

  23. Tomikawa, C., Yokogawa, T., Kanai, T. & Hori, H. N 7-Methylguanine at position 46 (m7G46) in tRNA from Thermus thermophilus is required for cell viability at high temperatures through a tRNA modification network. Nucleic Acids Res. 38, 942–957 (2010).

    CAS  PubMed  Google Scholar 

  24. Ikeuchi, Y. et al. Agmatine-conjugated cytidine in a tRNA anticodon is essential for AUA decoding in archaea. Nat. Chem. Biol. 6, 277–282 (2010).

    CAS  PubMed  Google Scholar 

  25. Ishida, K. et al. Pseudouridine at position 55 in tRNA controls the contents of other modified nucleotides for low-temperature adaptation in the extreme-thermophilic eubacterium Thermus thermophilus. Nucleic Acids Res. 39, 2304–2318 (2011).

    CAS  PubMed  Google Scholar 

  26. Kawamura, T., Anraku, R., Hasegawa, T., Tomikawa, C. & Hori, H. Transfer RNA methyltransferases from Thermoplasma acidophilum, a thermoacidophilic archaeon. Int. J. Mol. Sci. 16, 91–113 (2014).

    PubMed  PubMed Central  Google Scholar 

  27. Takuma, H. et al. Substrate tRNA recognition mechanism of eubacterial tRNA (m1A58) methyltransferase (TrmI). J. Biol. Chem. 290, 5912–5925 (2015).

    CAS  PubMed  PubMed Central  Google Scholar 

  28. Nomura, Y., Ohno, S., Nishikawa, K. & Yokogawa, T. Correlation between the stability of tRNA tertiary structure and the catalytic efficiency of a tRNA-modifying enzyme, archaeal tRNA-guanine transglycosylase. Genes Cells 21, 41–52 (2016).

    CAS  PubMed  Google Scholar 

  29. Yokogawa, T., Kitamura, Y., Nakamura, D., Ohno, S. & Nishikawa, K. Optimization of the hybridization-based method for purification of thermostable tRNAs in the presence of tetraalkylammonium salts. Nucleic Acids Res. 38, e89 (2010).

    PubMed  Google Scholar 

  30. Nomura, Y. et al. Purification and comparison of native and recombinant tRNA-guanine transglycosylases from Methanosarcina acetivorans. Protein Expr. Purif. 88, 13–19 (2013).

    CAS  PubMed  Google Scholar 

  31. Wishart, D. S. et al. HMDB: a knowledgebase for the human metabolome. Nucleic Acids Res. 37, D603–D610 (2009).

    CAS  PubMed  Google Scholar 

  32. Sofia, H. J., Chen, G., Hetzler, B. G., Reyes-Spindola, J. F. & Miller, N. E. Radical SAM, a novel protein superfamily linking unresolved steps in familiar biosynthetic pathways with radical mechanisms: functional characterization using new analysis and information visualization methods. Nucleic Acids Res. 29, 1097–1106 (2001).

    CAS  PubMed  PubMed Central  Google Scholar 

  33. Kanehisa, M., Sato, Y., Kawashima, M., Furumichi, M. & Tanabe, M. KEGG as a reference resource for gene and protein annotation. Nucleic Acids Res. 44, D457–D462 (2016).

    CAS  PubMed  Google Scholar 

  34. Sawai, H. Preparation of RPC-5 like resin for HPLC (Neosorb LC) and its use for the separation of oligonucleotides and mononucleotides. Nucleic Acids Symp. Ser. 15, 105–108 (1984).

    CAS  Google Scholar 

  35. Zhang, Y. et al. Diphthamide biosynthesis requires an organic radical generated by an iron-sulphur enzyme. Nature 465, 891–896 (2010).

    CAS  PubMed  PubMed Central  Google Scholar 

  36. Selvadurai, K., Wang, P., Seimetz, J. & Huang, R. H. Archaeal Elp3 catalyzes tRNA wobble uridine modification at C5 via a radical mechanism. Nat. Chem. Biol. 10, 810–812 (2014).

    CAS  PubMed  PubMed Central  Google Scholar 

  37. Young, A. P. & Bandarian, V. Pyruvate is the source of the two carbons that are required for formation of the imidazoline ring of 4-demethylwyosine. Biochemistry 50, 10573–10575 (2011).

    CAS  PubMed  PubMed Central  Google Scholar 

  38. Pierrel, F., Björk, G. R., Fontecave, M. & Atta, M. Enzymatic modification of tRNAs: MiaB is an iron–sulfur protein. J. Biol. Chem. 277, 13367–13370 (2002).

    CAS  PubMed  Google Scholar 

  39. Arragain, S. et al. Identification of eukaryotic and prokaryotic methylthiotransferase for biosynthesis of 2-methylthio-N 6-threonylcarbamoyladenosine in tRNA. J. Biol. Chem. 285, 28425–28433 (2010).

    CAS  PubMed  PubMed Central  Google Scholar 

  40. Toh, S.-M., Xiong, L., Bae, T. & Mankin, A. S. The methyltransferase YfgB/RlmN is responsible for modification of adenosine 2503 in 23S rRNA. RNA 14, 98–106 (2008).

    CAS  PubMed  PubMed Central  Google Scholar 

  41. Benítez-Páez, A., Villarroya, M. & Armengod, M.-E. The Escherichia coli RlmN methyltransferase is a dual-specificity enzyme that modifies both rRNA and tRNA and controls translational accuracy. RNA 18, 1783–1795 (2012).

    PubMed  PubMed Central  Google Scholar 

  42. Galperin, M. Y., Makarova, K. S., Wolf, Y. I. & Koonin, E. V. Expanded microbial genome coverage and improved protein family annotation in the COG database. Nucleic Acids Res. 43, D261–D269 (2015).

    CAS  PubMed  Google Scholar 

  43. Sato, T., Fukui, T., Atomi, H. & Imanaka, T. Improved and versatile transformation system allowing multiple genetic manipulations of the hyperthermophilic archaeon Thermococcus kodakaraensis. Appl. Environ. Microbiol. 71, 3889–3899 (2005).

    CAS  PubMed  PubMed Central  Google Scholar 

  44. Sato, T., Fukui, T., Atomi, H. & Imanaka, T. Targeted gene disruption by homologous recombination in the hyperthermophilic archaeon Thermococcus kodakaraensis KOD1. J. Bacteriol. 185, 210–220 (2003).

    CAS  PubMed  PubMed Central  Google Scholar 

  45. Atomi, H., Fukui, T., Kanai, T., Morikawa, M. & Imanaka, T. Description of Thermococcus kodakaraensis sp. nov., a well studied hyperthermophilic archaeon previously reported as Pyrococcus sp. KOD1. Archaea 1, 263–267 (2004).

    CAS  PubMed  PubMed Central  Google Scholar 

  46. Ochman, H., Gerber, A. S. & Hartl, D. L. Genetic applications of an inverse polymerase chain reaction. Genetics 120, 621–623 (1988).

    CAS  PubMed  PubMed Central  Google Scholar 

  47. Nagaoka, E., Hidese, R., Imanaka, T. & Fujiwara, S. Importance and determinants of induction of cold-induced DEAD RNA helicase in the hyperthermophilic archaeon Thermococcus kodakarensis. J. Bacteriol. 195, 3442–3450 (2013).

    CAS  PubMed  PubMed Central  Google Scholar 

  48. Hirata, A. et al. Archaeal RNA polymerase subunits E and F are not required for transcription in vitro, but a Thermococcus kodakarensis mutant lacking subunit F is temperature-sensitive. Mol. Microbiol. 70, 623–633 (2008).

    CAS  PubMed  PubMed Central  Google Scholar 

  49. Taniguchi, N., Nakayama, S., Kawakami, T. & Murakami, H. Patch cloning method for multiple site-directed and saturation mutagenesis. BMC Biotechnol. 13, 91 (2013).

    CAS  PubMed  PubMed Central  Google Scholar 

  50. Ikeda-Boku, A. et al. A simple system for expression of proteins containing 3-azidotyrosine at a pre-determined site in Escherichia coli. J. Biochem. 153, 317–326 (2013).

    CAS  PubMed  Google Scholar 

  51. Gasteiger, E et al. in The Proteomics Protocols Handbook (ed. Walker, J.M.) Ch. 52, 571–601 (Humana Press, 2005).

  52. Milligan, J. F., Groebe, D. R., Witherell, G. W. & Uhlenbeck, O. C. Oligoribonucleotide synthesis using T7 RNA polymerase and synthetic DNA templates. Nucleic Acids Res. 15, 8783–8798 (1987).

    CAS  PubMed  PubMed Central  Google Scholar 

  53. Nishimura, S., Harada, F., Narushima, U. & Seno, T. Purification of methionine-, valine-, phenylalanine- and tyrosine-specific tRNA from Escherichia coli. Biochim. Biophys. Acta 142, 133–148 (1967).

    CAS  PubMed  Google Scholar 

  54. Ehresmann, B., Imbault, P. & Weil, J. H. Spectrophotometric determination of protein concentration in cell extracts containing tRNA’s and rRNA’s. Anal. Biochem. 54, 454–463 (1973).

    CAS  PubMed  Google Scholar 

  55. Jones, B. N., Pääbo, S. & Stein, S. Amino acid analysis and enzymatic sequence determination of peptides by an improved o-phthaldialdehyde precolumn labeling procedure. J. Liq. Chromatogr. 4, 565–586 (1981).

    CAS  Google Scholar 

Download references

Acknowledgements

We are grateful to T. Inuzuka, O. Sakurada, S. Obata, Y. Onda, A. Izumoto, T. Okuda, M. Osawa and H. Miyawaki for technical assistance. This work was supported by JSPS KAKENHI grants JP16H04763 (to H.H.), JP17K05929 (to N.O.) and JP18K06088 (to A.H.), and the Koshiyama Science and Technology Foundation (to T.Y.). We thank J. Allen from Edanz Group (https://www.edanzediting.com/ac/) for editing a draft of this manuscript.

Author information

Authors and Affiliations

Authors

Contributions

T.Y. prepared the preQ0Lys-nucleotide for NMR. Y.N. and A.Y. performed the series of experiments on ArcS. H.O. prepared and analyzed tRNAs and proteins. K.H. and S.N. performed the series of experiments on M. acetivorans and T. kodakarensis ArcS–RaSEA, respectively. N.O. measured NMR of the preQ0Lys-nucleotide and synthesized q0kN under the supervision of K.A. T.K. and A.H. constructed the series of T. kodakarensis strains under the supervision of H.H. S.O. performed MS analysis. All authors discussed the results and commented on the manuscript. T.Y. designed and supervised all the work.

Corresponding author

Correspondence to Takashi Yokogawa.

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 Information

Supplementary Tables 1 and 2, and Figs. 1–21

Reporting Summary

Supplementary Note

Synthetic procedures

Supplementary Dataset

Gene profiling of an enzyme involved in archaeosine synthesis

Rights and permissions

Reprints and permissions

About this article

Check for updates. Verify currency and authenticity via CrossMark

Cite this article

Yokogawa, T., Nomura, Y., Yasuda, A. et al. Identification of a radical SAM enzyme involved in the synthesis of archaeosine. Nat Chem Biol 15, 1148–1155 (2019). https://doi.org/10.1038/s41589-019-0390-7

Download citation

  • Received:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1038/s41589-019-0390-7

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