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.

Incorporation of a non-human glycan mediates human susceptibility to a bacterial toxin

Abstract

AB5 toxins comprise an A subunit that corrupts essential eukaryotic cell functions, and pentameric B subunits that direct target-cell uptake after binding surface glycans. Subtilase cytotoxin (SubAB) is an AB5 toxin secreted by Shiga toxigenic Escherichia coli (STEC)1, which causes serious gastrointestinal disease in humans2. SubAB causes haemolytic uraemic syndrome-like pathology in mice3 through SubA-mediated cleavage of BiP/GRP78, an essential endoplasmic reticulum chaperone4. Here we show that SubB has a strong preference for glycans terminating in the sialic acid N-glycolylneuraminic acid (Neu5Gc), a monosaccharide not synthesized in humans. Structures of SubB-Neu5Gc complexes revealed the basis for this specificity, and mutagenesis of key SubB residues abrogated in vitro glycan recognition, cell binding and cytotoxicity. SubAB specificity for Neu5Gc was confirmed using mouse tissues with a human-like deficiency of Neu5Gc and human cell lines fed with Neu5Gc. Despite lack of Neu5Gc biosynthesis in humans, assimilation of dietary Neu5Gc creates high-affinity receptors on human gut epithelia and kidney vasculature. This, and the lack of Neu5Gc-containing body fluid competitors in humans, confers susceptibility to the gastrointestinal and systemic toxicities of SubAB. Ironically, foods rich in Neu5Gc are the most common source of STEC contamination. Thus a bacterial toxin's receptor is generated by metabolic incorporation of an exogenous factor derived from food.

Access options

Rent or Buy article

Get time limited or full article access on ReadCube.

from$8.99

All prices are NET prices.

Figure 1: Structural analysis of SubB-sialic acid interactions and comparison with other AB 5 toxins.
Figure 2: Fluorescence microscopy and Neu5Gc-dependent cytotoxicity.
Figure 3: Neu5Gc-dependent binding of SubAB to human tissues and toxicity of SubAB in wild-type and Cmah-null mice.

Accession codes

Primary accessions

Protein Data Bank

Data deposits

The coordinates and structure factors for the SubB structures are deposited in Protein Data Bank under accession numbers 3DWA, 3DWP and 3DWQ. Raw glycan array data are available at http://www.functionalglycomics.org/glycomics/publicdata/selectedScreens.jsp.

References

  1. 1

    Paton, A. W., Srimanote, P., Talbot, U. M., Wang, H. & Paton, J. C. A new family of potent AB5 cytotoxins produced by Shiga toxigenic Escherichia coli . J. Exp. Med. 200, 35-46 (2004)

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  2. 2

    Paton, J. C. & Paton, A. W. Pathogenesis and diagnosis of Shiga toxin-producing Escherichia coli infections. Clin. Microbiol. Rev. 11, 450-479 (1998)

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  3. 3

    Wang, H., Paton, J. C. & Paton, A. W. Pathologic changes in mice induced by subtilase cytotoxin, a potent new Escherichia coli AB5 toxin that targets the endoplasmic reticulum. J. Infect. Dis. 196, 1093-1101 (2007)

    Article  CAS  PubMed  Google Scholar 

  4. 4

    Paton, A. W. & Beddoe, T. Thorpe, C.M., Whisstock, J.C., Wilce, M.C.J., Rossjohn, J., Talbot, U.M. and Paton J.C. AB5 subtilase cytotoxin inactivates the endoplasmic reticulum chaperone BiP. Nature 443, 548-552 (2006)

    ADS  Article  CAS  PubMed  Google Scholar 

  5. 5

    Sandvig, K. & van Deurs, B. Membrane traffic exploited by protein toxins. Annu. Rev. Cell Dev. Biol. 18, 1-24 (2002)

    Article  CAS  PubMed  Google Scholar 

  6. 6

    Lencer, W. I. & Tsai, B. The intracellular voyage of cholera toxin: going retro. Trends Biochem. Sci. 28, 639-645 (2003)

    Article  CAS  PubMed  Google Scholar 

  7. 7

    Crocker, P. R., Paulson, J. C. & Varki, A. Siglecs and their roles in the immune system. Nature Rev. Immunol. 7, 55-66 (2007)

    Article  CAS  Google Scholar 

  8. 8

    Neu, U., Woellner, K., Gauglitz, G. & Stehle, T. Structural basis of GM1 ganglioside recognition by simian virus 40. Proc. Natl Acad. Sci. USA 105, 5219-5224 (2008)

    ADS  Article  PubMed  Google Scholar 

  9. 9

    Murzin, A. G. OB (oligonucleotide/oligosaccharide binding)-fold: common structural and functional solution for non-homologous sequences. EMBO J. 12, 861-867 (1993)

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  10. 10

    Stein, P. E. et al. Structure of a pertussis toxin-sugar complex as a model for receptor binding. Nature Struct. Biol. 1, 591-596 (1994)

    Article  CAS  PubMed  Google Scholar 

  11. 11

    Merritt, E. A., Sixma, T. K., Kalk, K. H., van Zanten, B. A. & Hol, W. G. Galactose-binding site in Escherichia coli heat-labile enterotoxin (LT) and cholera toxin (CT). Mol. Microbiol. 13, 745-753 (1994)

    Article  CAS  PubMed  Google Scholar 

  12. 12

    Merritt, E. A. et al. Structural studies of receptor binding by cholera toxin mutants. Protein Sci. 6, 1516-1528 (1997)

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  13. 13

    Ling, H., Bast, D. & Brunton, J. L. &. R. e. a. d. R. J. Structure of the Shiga-like toxin I B-pentamer complexed with an analogue of its receptor Gb3. Biochemistry 37, 1777-1788 (1998)

    Article  CAS  PubMed  Google Scholar 

  14. 14

    Yahiro, K. et al. Identification and characterization of receptors for vacuolating activity of subtilase cytotoxin. Mol. Microbiol. 62, 480-490 (2006)

    Article  CAS  PubMed  Google Scholar 

  15. 15

    Hedlund, M. et al. N-glycolylneuraminic acid deficiency in mice: implications for human biology and evolution. Mol. Cell. Biol. 27, 4340-4346 (2007)

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  16. 16

    Varki, A. Multiple changes in sialic acid biology during human evolution. Glycoconjugate J. 10.1007/s10719-008-9183-z (7 September 2008)

  17. 17

    Tangvoranuntakul, P. et al. Human uptake and incorporation of an immunogenic nonhuman dietary sialic acid. Proc. Natl Acad. Sci. USA 100, 12045-12050 (2003)

    ADS  Article  CAS  PubMed  Google Scholar 

  18. 18

    Gagneux, P. et al. Proteomic comparison of human and great ape blood plasma reveals conserved glycosylation and differences in thyroid hormone metabolism. Am. J. Phys. Anthropol. 115, 99-109 (2001)

    Article  CAS  PubMed  Google Scholar 

  19. 19

    Talbot, U. M., Paton, J. C. & Paton, A. W. Protective immunization of mice with an active-site mutant of subtilase cytotoxin of Shiga toxin-producing Escherichia coli . Infect. Immun. 73, 4432-4436 (2005)

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  20. 20

    Chong, D. C., Paton, J. C., Thorpe, C. M. & Paton, A. W. Clathrin-dependent trafficking of subtilase cytotoxin, a novel AB5 toxin that targets the ER chaperone BiP. Cell. Microbiol. 10, 795-806 (2008)

    Article  CAS  PubMed  Google Scholar 

  21. 21

    Leslie, A. G. W. in Joint CCP4 and ESF-EACMB Newsletter on Protein Crystallography 26 (SERC, 1992)

    Google Scholar 

  22. 22

    Evans, P. R. in Proc. CCP4 Study Weekend on Recent Advances in Phasing 97-102 (CCLRC, 1997)

    Google Scholar 

  23. 23

    Collaborative Computational Project. Number 4. Acta Crystallogr. D 50, 760-763 (1994)

  24. 24

    Adams, P. D. et al. PHENIX: building new software for automated crystallographic structure determination. Acta Crystallogr. D 58, 1948-1954 (2002)

    MathSciNet  Article  CAS  PubMed  Google Scholar 

  25. 25

    Terwilliger, T. C. Automated main-chain model building by template matching and iterative fragment extension. Acta Crystallogr. D 59, 38-44 (2003)

    Article  CAS  PubMed  Google Scholar 

  26. 26

    Perrakis, A., Sixma, T. K., Wilson, K. S. & Lamzin, V. S. Warp: improvement and extension of crystallographic phases by weighted averaging of multiple refined dummy models. Acta Crystallogr. D 30, 551-554 (1997)

    Google Scholar 

  27. 27

    Emsley, P. & Cowtan, K. Coot: model-building tools for molecular graphics. Acta Crystallogr. D 60, 2126-2132 (2004)

    Article  CAS  PubMed  Google Scholar 

  28. 28

    Murshodov, G. N., Vagin, A. A. & Dodson, E. J. Refinement of macromolecular structures by the maximum likelihood method. Acta Crystallogr. D 53, 240-255 (1997)

    Article  Google Scholar 

  29. 29

    McCoy, A. J., Grosse-Kunstleve, R. W., Storoni, L. C. & Read, R. J. Likelihood-enhanced fast translation functions. Acta Crystallogr. D 61, 458-464 (2005)

    Article  CAS  PubMed  Google Scholar 

  30. 30

    Schuettelkopf, A. W. & van Aalten, D. M. F. PRODRG - a tool for high-throughput crystallography of protein-ligand complexes. Acta Crystallogr. D 60, 1355-1363 (2004)

    Article  CAS  Google Scholar 

Download references

Acknowledgements

We thank the staff at the General Medicine and Cancer Institutes Collaborative Access Team Advanced Photon Source, Chicago, for assistance with data collection. This research was supported by a Program Grant from the National Health and Medical Research Council of Australia (NHMRC; to A.W.P. and J.C.P.), an NHMRC Project Grant (to T.B. and A.W.P.), a grant from the National Institute of General Medical Sciences to the Consortium for Functional Glycomics, RO1 grants from the National Institutes of Health (to A.W.P., J.C.P., J.R., X.C. and A.V.) and from the ARC Centre of Excellence in Structural and Functional Microbial Genomics (to J.R.). J.R. is supported by an Australian Research Council Federation Fellowship; T.B. by an NHMRC Career Development Award; J.C.P. by an NHMRC Australia Fellowship. We also thank C. J. Gregg for assistance with in vivo experiments and with collection of data, and L. Wiggleton for technical assistance with tissue sectioning and staining.

Author Contributions E.B. and A.W.P. contributed equally. E.B, T.B. and M.C.J.W. crystallized SubB, solved the structure and contributed to manuscript preparation. A.W.P. constructed mutants and contributed to design and interpretation of experiments, project management and writing of the manuscript. J.C.P. and J.R. contributed to design and interpretation of experiments, project management and writing of the manuscript. D.C.C. and U.M.T. performed experiments. D.F.S. performed and interpreted glycan array experiments. J.C.L., N.M.V. and A.V. designed, performed and interpreted experiments relating to Neu5Gc on cells and tissues and to cytotoxicity in vivo, and contributed to manuscript preparation. H.Y., S.H. and X.C. synthesized oligosaccharides. A.V., T.B. and J.R. are joint senior and corresponding authors.

Author information

Affiliations

Authors

Corresponding authors

Correspondence to Ajit Varki or Jamie Rossjohn or Travis Beddoe.

Supplementary information

Supplementary Information

This file contains Supplementary Tables 1-5 and Supplementary Figures 1-2 with Legends (PDF 418 kb)

PowerPoint slides

Rights and permissions

Reprints and Permissions

About this article

Cite this article

Byres, E., Paton, A., Paton, J. et al. Incorporation of a non-human glycan mediates human susceptibility to a bacterial toxin. Nature 456, 648–652 (2008). https://doi.org/10.1038/nature07428

Download citation

Further reading

Comments

By submitting a comment you agree to abide by our Terms and Community Guidelines. If you find something abusive or that does not comply with our terms or guidelines please flag it as inappropriate.

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