A heterologous expression platform in Aspergillus nidulans for the elucidation of cryptic secondary metabolism biosynthetic gene clusters: discovery of the Aspergillus fumigatus sartorypyrone biosynthetic pathway
-
1.
California Institute of Technology
Abstract
Aspergillus fumigatus is a serious human pathogen causing life-threatening Aspergillosis in immunocompromised patients. Secondary metabolites (SMs) play an important role in pathogenesis, but the products of many SM biosynthetic gene clusters (BGCs) remain unknown. In this study, we have developed a heterologous expression platform in Aspergillus nidulans, using a newly created genetic dereplication strain, to express a previously unknown BGC from A. fumigatus and determine its products. The BGC produces sartorypyrones, and we have named it the spy BGC. Analysis of targeted gene deletions by HRESIMS, NMR, and microcrystal electron diffraction (MicroED) enabled us to identify 12 products from the spy BGC. Seven of the compounds have not been isolated previously. We also individually expressed the polyketide synthase (PKS) gene spyA and demonstrated that it produces the polyketide triacetic acid lactone (TAL), a potentially important biorenewable platform chemical. Our data have allowed us to propose a biosynthetic pathway for sartorypyrones and related natural products. This work highlights the potential of using the A. nidulans heterologous expression platform to uncover cryptic BGCs from A. fumigatus and other species, despite the complexity of their secondary metabolomes.
Additional Information
© 2023 The Author(s). Published by the Royal Society of Chemistry. This article is licensed under a Creative Commons Attribution-NonCommercial 3.0 Unported Licence. All publication charges for this article have been paid for by the Royal Society of Chemistry. S. L. acknowledges the financial support from National Defense Medical Center, Taiwan. B. R. O. and C. C. C. W. are supported by a grant R21AI156320 from the National Institute for Allergies and Infectious Diseases. B. R. O. is supported by the Irving S. Johnson Fund of the University of Kansas Endowment. Contribution number 23-271-J from the Kansas Agricultural Experiment Station. Data availability: All experimental procedures and characterization data are available in the ESI. The NMR spectra data are available in the Natural Products Magnetic Resonance Database (NP-MRD). Author contributions: C. C. C. W. and B. R. O. supervised the project. S. L. and C. E. O. performed all the experiments. S. L. completed data analysis. C. B. J. and R. B. T. contributed to the design of the experiments. S. L., Y. C.and C. L. contributed to the elucidation of the structures. The MicroED data collection and processing was performed by C. G. J. and P. M. S. with the help of H. M. N.; B. R. O. and R. B. T. contributed to data interpretation. The initial manuscript was written by S. L. with the help of R. B. T., C. C. C. W. and B. R. O. and all authors participated in reviewing and editing. The authors declare no conflicts of interest.Attached Files
Supplemental Material - d3sc02226a1.pdf
Supplemental Material - d3sc02226a2.cif
Supplemental Material - d3sc02226a3.cif
Files
Additional details
- Eprint ID
- 122338
- Resolver ID
- CaltechAUTHORS:20230717-55915200.34
- PMCID
- PMC10583710
- DOI
- 10.1039/d3sc02226a
- National Defense Medical Center (Taiwan)
- NIH
- R21AI156320
- University of Kansas
- Royal Society of Chemistry
- Created
-
2023-08-14Created from EPrint's datestamp field
- Updated
-
2023-08-14Created from EPrint's last_modified field
- Other Numbering System Name
- Kansas Agricultural Experiment Station
- Other Numbering System Identifier
- 23-271-J