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Chemoenzymatic synthesis of fluorinated polyketides


Modification of polyketides with fluorine offers a promising approach to develop new pharmaceuticals. While synthetic chemical methods for site-selective incorporation of fluorine in complex molecules have improved in recent years, approaches for the biosynthetic incorporation of fluorine in natural compounds are still rare. Here, we report a strategy to introduce fluorine into complex polyketides during biosynthesis. We exchanged the native acyltransferase domain of a polyketide synthase, which acts as the gatekeeper for the selection of extender units, with an evolutionarily related but substrate tolerant domain from metazoan type I fatty acid synthase. The resulting polyketide-synthase/fatty-acid-synthase hybrid can utilize fluoromalonyl coenzyme A and fluoromethylmalonyl coenzyme A for polyketide chain extension, introducing fluorine or fluoro-methyl units in polyketide scaffolds. We demonstrate the feasibility of our approach in the chemoenzymatic synthesis of fluorinated 12- and 14-membered macrolactones and fluorinated derivatives of the macrolide antibiotics YC-17 and methymycin.

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Fig. 1: Modular PKSs and hybrid design.
Fig. 2: Function of the hybrid DEBS/FAS modules.
Fig. 3: Enzymatic synthesis of 10-deoxymethynolide derivatives.
Fig. 4: Synthesis of new fluorinated macrolide antibiotics and 14-membered macrolactones.

Data availability

All data supporting the main findings of the article, including materials and methods, are described in the Article or Supplementary Information. Alternatively, the data are available from the corresponding author on request.


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This work was supported by a Lichtenberg grant of the Volkswagen Foundation to M.G. (grant number 85701). Further support was received from the LOEWE programme (Landes-Offensive zur Entwicklung wissenschaftlich-ökonomischer Exzellenz) of the state of Hesse conducted within the framework of the MegaSyn Research Cluster to M.G. We thank K. V. Huu and K. Karimi for MS analysis of acyl carrier proteins and K. S. Paithankar for proofreading the manuscript. Further, we are grateful to the Bode group for the extensive support in HPLC-MS and HPLC-HRMS analysis and J. Wirmer-Bartoschek and G. Sentis for support in NMR analysis. D.H.S. is grateful to National Institutes of Health grant R35 GM118101 and the Hans W. Vahlteich Professorship for support.

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Authors and Affiliations



A.R. conceived and supervised the project. M.G. and D.H.S. designed the research. A.R. and D.H. performed the expression, purification and mutagenesis of murine KS–MAT constructs. L.M.M. performed global kinetic experiments (with F-Mal-CoA and MM-CoA) and analysed corresponding data under the supervision of A.R.; S.R. performed global kinetic experiments (with F-MM-CoA) and analysed corresponding data under the supervision of M.J.; A.R. and M.J. designed DEBS/FAS hybrids. M.J. performed the expression, purification and analysis of DEBS M6 constructs with respective MS analysis. M.J. and E.H. performed substrate consumption assays by HPLC with ultraviolet spectroscopy. F-Mal-CoA and F-MM-CoA were synthesized by A.R., and the diketide SNAC was synthesized by M.J. Pentaketide and hexaketide substrates were synthesized by J.J.S.; A.R. and M.J. performed semi-synthesis and analysis of compounds 12, (14, 15), 16, 18, 22 and 23 and analysed all data. S.R. performed semi-synthesis of 18 with H1.1 under the supervision of M.J.; J.J.S. performed the biotransformation of compound 18 and analysed data. A.R., M.J., J.J.S., D.H.S. and M.G. wrote the manuscript.

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Correspondence to Martin Grininger.

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A.R. declares a financial interest as a cofounder of kez.biosolutions GmbH (Potsdam, Germany). All other authors declare no competing interests.

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Nature Chemistry thanks Constance Bailey, Binuraj Menon and the other, anonymous, reviewer(s) for their contribution to the peer review of this work.

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Supplementary Figs. 1–24, Tables 1–6, Materials and Methods, notes, spectra and references.

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Rittner, A., Joppe, M., Schmidt, J.J. et al. Chemoenzymatic synthesis of fluorinated polyketides. Nat. Chem. 14, 1000–1006 (2022).

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