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The bacterial conjugation protein TrwB resembles ring helicases and F1-ATPase

Nature volume 409, pages 637–641 (2001)Cite this article

Abstract

The transfer of DNA across membranes and between cells is a central biological process; however, its molecular mechanism remains unknown. In prokaryotes, trans-membrane passage by bacterial conjugation, is the main route for horizontal gene transfer. It is the means for rapid acquisition of new genetic information, including antibiotic resistance by pathogens. Trans-kingdom gene transfer from bacteria to plants1 or fungi2 and even bacterial sporulation3 are special cases of conjugation. An integral membrane DNA-binding protein, called TrwB in the Escherichia coli R388 conjugative system, is essential for the conjugation process. This large multimeric protein is responsible for recruiting the relaxosome DNA–protein complex, and participates in the transfer of a single DNA strand during cell mating. Here we report the three-dimensional structure of a soluble variant of TrwB. The molecule consists of two domains: a nucleotide-binding domain of α/β topology, reminiscent of RecA and DNA ring helicases, and an all-α domain. Six equivalent protein monomers associate to form an almost spherical quaternary structure that is strikingly similar to F1-ATPase. A central channel, 20 Å in width, traverses the hexamer.

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Figure 1: Structural features of TrwB.
Figure 2: Electrostatic surface representations.

References

  1. Stachel, S. E. & Zambryski, P. Agrobacterium tumefaciens and the susceptible plant cell: a novel adaptation of extracellular recognition and DNA conjugation. Cell 47, 155–157 (1986).

    Article  CAS  Google Scholar 

  2. Heinemann, J. A. & Sprague, G. F. J. Bacterial conjugative plasmids mobilize DNA transfer between bacteria and yeast. Nature 340, 205–209 (1989).

    Article  ADS  CAS  Google Scholar 

  3. Wu, L. J., Lewis, P. J., Allmansberger, R., Hauser, P. M. & Errington, J. A conjugation-like mechanism for prespore chromosome partitioning during sporulation in Bacillus subtilis. Gene Dev. 9, 1316–1326 (1995).

    Article  CAS  Google Scholar 

  4. Llosa, M., Bolland, S. & de la Cruz, F. Genetic organization of the conjugal DNA processing region of the IncW plasmid R388. J. Mol. Biol. 235, 448–464 (1994).

    Article  CAS  Google Scholar 

  5. Moncalián, G. et al. Characterization of ATP and DNA binding activities of TrwB, the coupling protein essential in plasmid R388 conjugation. J. Biol. Chem. 274, 36117–36124 (1999).

    Article  Google Scholar 

  6. Zechner, E. L. in The Horizontal Gene Pool: Bacterial Plasmids and Gene Spread (ed. Thomas, C. M.) 87–173 (Harwood Academic, London, 2000).

    Google Scholar 

  7. Cabezón, E., Sastre, J. I. & de la Cruz, F. Genetic evidence of a coupling role for the TraG protein family in bacterial conjugation. Mol. Gen. Genet. 254, 400–406 (1997).

    Article  Google Scholar 

  8. Begg, K. J., Dewar, S. J. & Donachie, W. D. A new Escherichia coli cell division gene, ftsK. J. Bacteriol. 177, 6211–6222 (1995).

    Article  CAS  Google Scholar 

  9. Walker, J. E., Saraste, M., Runswick, M. J. & Gay, N. J. Distantly related sequences in the α- and β-subunits of ATP synthase, myosin, kinases and other ATP-requiring enzymes and a common nucleotide binding fold. EMBO J. 1, 945–951 (1982).

    Article  CAS  Google Scholar 

  10. Abrahams, J. P., Leslie, A. G. W., Lutter, R. & Walker, J. E. Structure at 2.8 Å resolution of F1-ATPase from bovine heart mitochondria. Nature 370, 621–628 (1994).

    Article  ADS  CAS  Google Scholar 

  11. Singleton, M. R., Sawaya, M. R., Ellenberger, T. & Wigley, D. B. Crystal structure of T7 gene 4 ring helicase indicates a mechanism for sequential hydrolysis of nucleotides. Cell 101, 589–600 (2000).

    Article  CAS  Google Scholar 

  12. Story, R. M., Weber, I. T. & Steitz, T. A. The structure of the E.coli recA protein monomer and polymer. Nature 355, 318–325 (1992).

    Article  ADS  CAS  Google Scholar 

  13. Sawaya, M. R., Guo, S., Tabor, S., Richardson, C. C. & Ellenberger, T. Crystal structure of the helicase domain from the replicative helicase-primase of bacteriophage T7. Cell 99, 167–177 (1999).

    Article  CAS  Google Scholar 

  14. Guenther, B., Onrust, R., Sali, A., O'Donnell, M. & Kuriyan, J. Crystal structure of the δ′ subunit of the clamp-loader complex of E.coli DNA polymerase III. Cell 91, 335–345 (1997).

    Article  CAS  Google Scholar 

  15. Lenzen, C. U., Steinmann, D., Whiteheart, S. W. & Weis, W. I. Crystal structure of the hexamerization domain of N-ethylmaleimide-sensitive fusion protein. Cell 94, 525–535 (1998).

    Article  CAS  Google Scholar 

  16. Subramanya, H. S., Bird, L. E., Brannigan, J. A. & Wigley, D. B. Crystal structure of a DExx box DNA helicase. Nature 384, 379–383 (1996).

    Article  ADS  CAS  Google Scholar 

  17. Subramanya, H. S. et al. Crystal structure of the site-specific recombinase, XerD. EMBO J. 16, 5178–5187 (1997).

    Article  CAS  Google Scholar 

  18. Egelman, E. H., Yu, X., Wild, R., Hingorani, M. M. & Patel, S. M. Bacteriophage T7 helicase/primase proteins form rings around single-stranded DNA that suggest a general structure for hexameric helicases. Proc. Natl Acad. Sci. USA 92, 3869–3873 (1995).

    Article  ADS  CAS  Google Scholar 

  19. Hacker, K. J. & Johnson, K. A. A hexameric helicase encircles one DNA strand and excludes the other during DNA unwinding. Biochemistry 36, 14080-14087 (1997).

    Article  Google Scholar 

  20. Yu, X., Hingorani, M. M., Patel, S. S. & Egelman, E. H. DNA is bound within the central hole to one or two of the six subunits of the T7 DNA helicase. Nature Struct. Biol. 3, 740–743 (1996).

    Article  CAS  Google Scholar 

  21. Soultanas, P. & Wigley, D. B. DNA helicases: ‘inching forward’. Curr. Opin. Struct. Biol. 10, 124–128 (2000).

    Article  CAS  Google Scholar 

  22. Raney, K. D. & Benkovic, S. J. Bacteriophage T4 DDA helicase translocates in an unidirectional fashion on single-stranded DNA. J. Biol. Chem. 270, 22236–22242 (1995).

    Article  CAS  Google Scholar 

  23. Kaplan, D. L. The 3′-tail of a forked-duplex sterically determines whether one or two DNA strands pass through the central channel of a replication-fork helicase. J. Mol. Biol. 301, 285–299 (2000).

    Article  CAS  Google Scholar 

  24. Leslie, A. G. W. in Crystallographic computing V (eds Moras, D., Podjarny, A. D. & Thierry, J. C.) 27–38 (Oxford Univ. Press, Oxford, 1991).

    Google Scholar 

  25. CCP4. The CCP4 suite: programs for protein crystallography. Acta Crystallogr. D 50, 760–763 (1994).

    Article  Google Scholar 

  26. Sheldrick, G. M. Patterson superposition and ab initio phasing. Methods Enzymol. 276, 628–641 (1997).

    Article  CAS  Google Scholar 

  27. Brünger, A. T. et al. Crystallography & NMR System: a new software suite for macromolecular structure determination. Acta Crystallogr. D 54, 905–921 (1998).

    Article  Google Scholar 

  28. Navaza, J. AMoRe: an automated package for molecular replacement. Acta Crystallogr. A 50, 157–163 (1994).

    Article  Google Scholar 

  29. Evans, S. V. SETOR: hardware lighted three-dimensional solid model representations of macromolecules. J. Mol. Graphics 11, 134–138 (1993).

    Article  CAS  Google Scholar 

  30. Nicholls, A., Bharadwaj, R. & Honig, B. GRASP: graphical representation and analysis of surface properties. Biophys. J. 64, A166–A166 (1993).

    Google Scholar 

  31. Sastre, J. I., Cabezon, E. & de la Cruz, F. The carboxyl terminus of protein TraD adds specificity and efficiency to F-plasmid conjugative transfer. J. Bacteriol. 180, 6039–6042 (1998).

    CAS  PubMed  PubMed Central  Google Scholar 

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Acknowledgements

We are most grateful to R. Huber for making tantalum bromide available to us, and to I. Usón for help with SHELX. This work was supported by grants from the Ministerio de Educación y Cultura of Spain, the Generalitat de Catalunya and the European Union. Synchrotron data collection was supported by EU grants and the ESRF.

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Author notes

  1. Ana González

    Present address: Stanford Linear Accelerator Center, 2575 Sand Hill Road, Mail Stop 99, Menlo Park, California, 94025, USA

Authors and Affiliations

  1. Institut de Biologia Molecular de Barcelona, CSIC, Jordi Girona, 18-26, Barcelona, 08034, Spain

    F. Xavier Gomis-Rüth, Rosa Pérez-Luque & Miquel Coll

  2. Departamento de Biología Molecular (Laboratorio asociado al CIB, CSIC), Universidad de Cantabria, Herrera Oria, 39011, Santander, Spain

    Gabriel Moncalián, Elena Cabezón & Fernando de la Cruz

  3. EMBL Hamburg Outstation, c/o DESY, Notkestrasse 85, Hamburg, 22603, Germany

    Ana González

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Correspondence to Miquel Coll.

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Gomis-Rüth, F., Moncalián, G., Pérez-Luque, R. et al. The bacterial conjugation protein TrwB resembles ring helicases and F1-ATPase. Nature 409, 637–641 (2001). https://doi.org/10.1038/35054586

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