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.

  • Letter
  • Published:

A chain initiation factor common to both modular and aromatic polyketide synthases

Nature volume 401, pages 502–505 (1999)Cite this article

Abstract

Antibiotic-producing polyketide synthases (PKSs) are enzymes responsible for the biosynthesis in Streptomyces and related filamentous bacteria of a remarkably broad range of bioactive metabolites, including antitumour aromatic compounds such as mithramycin1 and macrolide antibiotics such as erythromycin2. The molecular basis for the selection of the starter unit on aromatic PKSs is unknown3. Here we show that a component of aromatic PKS, previously named ‘chain-length factor’4, is a factor required for polyketide chain initiation and that this factor has decarboxylase activity towards malonyl-ACP (acyl carrier protein). We have re-examined the mechanism of initiation on modular PKSs and have identified as a specific initiation factor a domain of previously unknown function named KSQ, which operates like chain-length factor. Both KSQ and chain-length factor are similar to the ketosynthase domains that catalyse polyketide chain extension in modular multifunctional PKSs and in aromatic PKSs, respectively, except that the ketosynthase domain active-site cysteine residue is replaced by a highly conserved glutamine in KSQ and in chain-length factor. The glutamine residue is important both for decarboxylase activity and for polyketide synthesis.

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

Access options

Buy this article

  • Purchase on Springer Link
  • Instant access to full article PDF
Buy now

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

Figure 1: Decarboxylation of malonyl-ACP on KS, KSQ and CLF domains.
Figure 2: Active-site sequences of typical KS and CLF subunits from type II PKSs and KS and KSQ domains from type I PKSs.
Figure 3: Functional analysis of KS/CLF and KSQ.
Figure 4: Conversion of malonyl-ACP to acetyl-ACP and polyketide production by KS/CLF mutants at 30 °C.

Similar content being viewed by others

References

  1. Lombó,F. et al. Cloning and insertional inactivation of Streptomyces argillaceus genes involved in the earliest steps of biosynthesis of the sugar moieties of the antitumor polyketide mithramycin. J. Bacteriol. 179, 3354–3357 (1997).

    Article  Google Scholar 

  2. Staunton,J. & Wilkinson,B. The biosynthesis of aliphatic polyketides. Topics Curr. Chem. 195, 49–92 (1998).

    Article  CAS  Google Scholar 

  3. Hopwood,D. A. Genetic contributions to understanding polyketide synthases. Chem. Rev. 97, 2465–2497 (1997).

    Article  CAS  Google Scholar 

  4. McDaniel,R., Ebert-Khosla,S., Hopwood,D. A. & Khosla,C. Engineered biosynthesis of novel polyketides. Science 262, 1546–1550 (1993).

    Article  ADS  CAS  Google Scholar 

  5. McDaniel,R., Ebert-Khosla,S., Fu,H., Hopwood,D. A. & Khosla,C. Engineered biosynthesis of novel polyketides: influence of a downstream enzyme on the catalytic specificity of a minimal aromatic polyketide synthase. Proc. Natl Acad. Sci. USA 91, 11542–11546 (1994).

    Article  ADS  CAS  Google Scholar 

  6. McDaniel,R., Ebert-Khosla,S., Hopwood,D. A. & Khosla,C. Rational design of aromatic polyketide natural products by recombinant assembly of enzymatic subunits. Nature 375, 549–554 (1995).

    Article  ADS  CAS  Google Scholar 

  7. Shen,B., Summers,R. G., Wendt-Pienkowski,E. & Hutchinson,C. R. The Streptomyces glaucescens tcm KL polyketide synthase and tcmN polyketide cyclase genes govern the size and shape of aromatic polyketides. J. Am. Chem. Soc. 117, 6811–6821 (1995).

    Article  CAS  Google Scholar 

  8. Kramer,P. J. et al. Rational design and engineered biosynthesis of a novel 18-carbon aromatic polyketide. J. Am. Chem. Soc. 119, 635–639 (1997).

    Article  CAS  Google Scholar 

  9. Yu,T. W. et al. Engineered biosynthesis of novel polyketides from Streptomyces spore pigment polyketide synthases. J. Am. Chem. Soc. 120, 7749–7759 (1998).

    Article  CAS  Google Scholar 

  10. Zawada,R. J. X. & Khosla,C. Domain analysis of the molecular recognition features of aromatic polyketide synthase subunits. J. Biol. Chem. 272, 16184–16188 (1997).

    Article  CAS  Google Scholar 

  11. Carreras,C. W. & Khosla,C. Purificaton and in vitro reconstitution of the essential protein components of an aromatic polyketide synthase. Biochemistry 37, 2084–2088 (1998).

    Article  CAS  Google Scholar 

  12. Bao,W. L., Wendt-Pienkowski,E. & Hutchinson,C. R. Reconstitution of the iterative type II polyketide synthase for tetracenomycin F2 biosynthesis. Biochemistry 37, 8132–8138 (1998).

    Article  CAS  Google Scholar 

  13. Matharu, A.-L., Cox,R. J., Crosby,J., Byrom,K. J. & Simpson,T. J. MCAT is not required for in vitro polyketide synthesis in a minimal actinorhodin polyketide synthase from Streptomyces coelicolor. Chem. Biol. 5, 699–711 (1998).

    Article  Google Scholar 

  14. Hitchman,T. S., Crosby,J., Byrom,K. J., Cox,R. J. & Simpson,T. J. Catalytic self-acylation of type II polyketide synthase acyl carrier proteins. Chem. Biol. 5, 35–47 (1998).

    Article  CAS  Google Scholar 

  15. Kresze, G.-B., Steber,L., Oesterhelt,D. & Lynen,F. Reaction of yeast fatty acid synthetase with iodoacetamide. Eur. J. Biochem. 79, 191–199 (1977).

    Article  Google Scholar 

  16. Pieper,R., Gokhale,R. S., Luo,G. L., Cane,D. E. & Khosla,C. Purification and characterization of biomodular and trimodular derivatives of the erythromycin polyketide synthase. Biochemistry 36, 1846–1851 (1997).

    Article  CAS  Google Scholar 

  17. Siggaard-Andersen,M. Conserved residues in condensing enzyme domains of fatty acid synthases and related sequences. Protein Seq. Data Anal. 5, 325–335 (1993).

    CAS  Google Scholar 

  18. Kim,E. S., Cramer,K. D., Shreve,A. L. & Sherman,D. H. Heterologous expression of an engineered biosynthetic pathway: functional dissection of type II polyketide synthase components in Streptomyces species. J. Bacteriol. 177, 1202–1207 (1995).

    Article  CAS  Google Scholar 

  19. Meurer,G. & Hutchinson,C. R. Functional analysis of putative β-ketoacyl:acyl carrier protein synthase and acyltransferase active site motifs in a type II polyketide synthase of Streptomyces glaucescens. J. Bacteriol. 177, 477–481 (1995).

    Article  CAS  Google Scholar 

  20. Joshi,A. K., Witkowski,A. & Smith,S. Mapping of functional interactions between domains of the animal fatty acid synthase by mutant complementation in vitro. Biochemistry 36, 2316–2322 (1997).

    Article  CAS  Google Scholar 

  21. Wiesmann,K. E. H. et al. Polyketide synthesis in vitro on a modular polyketide synthase. Chem. Biol. 2, 583–589 (1995).

    Article  CAS  Google Scholar 

  22. Pieper,R., Luo,G. L., Cane,D. E. & Khosla,C. Remarkably broad substrate specificity of a modular polyketide synthase in a cell-free system. J. Am. Chem. Soc. 117, 11373–11374 (1995).

    Article  CAS  Google Scholar 

  23. Kao,C. M., Pieper,R., Cane,D. E. & Khosla,C. Evidence for two catalytically independent clusters of active sites in a functional modular polyketide synthase. Biochemistry 35, 12363–12368 (1996).

    Article  CAS  Google Scholar 

  24. Weissman,K. J., Bycroft,M., Staunton,J. & Leadlay,P. F. Origin of starter units for erythromycin biosynthesis. Biochemistry 37, 11012–11017 (1998).

    Article  CAS  Google Scholar 

  25. Marsden,A. F. A. et al. Engineering broader specificity into an antibiotic-producing polyketide synthase. Science 279, 199–202 (1998).

    Article  ADS  CAS  Google Scholar 

  26. Rowe,C. J., Cortés,J., Gaisser,S., Staunton,J. & Leadlay,P. F. Construction of new vectors for high-level expression in actinomycetes. Gene 216, 215–223 (1998).

    Article  CAS  Google Scholar 

  27. Crosby,J. et al. Polyketide synthase acyl carrier proteins from Streptomyces: expression in Escherichia coli, purification and partial characterization. Biochim. Biophys. Acta 1251, 32–42 (1995).

    Article  Google Scholar 

Download references

Acknowledgements

This work was supported by grants from the BBSRC (UK) (to J.S. and P.F.L., and to T.J.S.), from the EPSRC (UK) (studentship to J.W.), from the Swiss National Science Foundation (to C.B.) and from Pfizer Inc. We thank H. A. I. McArthur, M. Oliynyk and C. J. Wilkinson for helpful advice.

Author information

Author notes

  1. Paul F. Long

    Present address: School of Pharmacy, University of Wisconsin, 425N Charter Street, Madison, Wisconsin, 53706, USA

  2. Jesús Corte´s

    Present address: Glaxo Wellcome Research and Development, Medicines Research Centre, Gunnels Wood Road, Stevenage, Hartfordshire, SG1 2NY, UK

  3. Christian Bisang, Paul F. Long, James Westcott, John Crosby, Anne-Lise Matharu, Russell J. Cox and Thomas J. Simpson: These authors contributed equally to this work

Authors and Affiliations

  1. Department of Biochemistry, 80 Tennis Court Road, Cambridge, CB2 1GA, UK

    Christian Bisang, Paul F. Long, Jesús Corte´s & Peter F. Leadlay

  2. School of Chemistry, University of Bristol, Cantock's Close, Bristol, BS8 1TS, UK

    James Westcott, John Crosby, Anne-Lise Matharu, Russell J. Cox & Thomas J. Simpson

  3. University Chemical Laboratory, Lensfield Road, Cambridge, CB2 1EW, UK

    James Staunton

Authors
  1. Christian Bisang
    View author publications

    You can also search for this author in PubMed Google Scholar

  2. Paul F. Long
    View author publications

    You can also search for this author in PubMed Google Scholar

  3. Jesús Corte´s
    View author publications

    You can also search for this author in PubMed Google Scholar

  4. James Westcott
    View author publications

    You can also search for this author in PubMed Google Scholar

  5. John Crosby
    View author publications

    You can also search for this author in PubMed Google Scholar

  6. Anne-Lise Matharu
    View author publications

    You can also search for this author in PubMed Google Scholar

  7. Russell J. Cox
    View author publications

    You can also search for this author in PubMed Google Scholar

  8. Thomas J. Simpson
    View author publications

    You can also search for this author in PubMed Google Scholar

  9. James Staunton
    View author publications

    You can also search for this author in PubMed Google Scholar

  10. Peter F. Leadlay
    View author publications

    You can also search for this author in PubMed Google Scholar

Corresponding author

Correspondence to Paul F. Long.

Rights and permissions

Reprints and permissions

About this article

Cite this article

Bisang, C., Long, P., Corte´s, J. et al. A chain initiation factor common to both modular and aromatic polyketide synthases. Nature 401, 502–505 (1999). https://doi.org/10.1038/46829

Download citation

  • Received:

  • Accepted:

  • Issue Date:

  • DOI: https://doi.org/10.1038/46829

This article is cited by

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

Advanced 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