Identification of a fungal antibacterial endopeptidase that cleaves peptidoglycan
Aspergillus fumigatus is a saprophytic fungus dwelling in soil and on decaying plant material, but also an opportunistic pathogen in immunocompromised patients. In its environmental niche, A. fumigatus faces competition from other microorganisms including bacteria. Here, we describe the discovery of the first secreted antibacterial protein in A. fumigatus. We identify a secreted fungal endopeptidase, designated CwhA, that cleaves peptidoglycan of Gram-positive bacteria at specific residues within the peptidoglycan stem peptide. Cleavage leads to bacterial lysis and the release of peptidoglycan cleavage products. Expression of cwhA is induced by the presence of bacteria. Furthermore, CwhA is highly abundant in murine lungs during invasive pulmonary aspergillosis and peptidoglycan cleavage products generated by CwhA stimulate cytokine production of human immune cells in vitro. Although CwhA does not affect human cells directly, this novel player in fungal-bacterial interactions could affect A. fumigatus infections by inhibiting Gram-positive bacteria in its vicinity, and possibly modulate the immune system.
Authors
- Franziska Kage
- Ute Bertsche (ORCID: https://orcid.org/0000-0002-1897-5557)
- Hortense Slevogt (ORCID: https://orcid.org/0000-0001-7104-9547)
- Ilse D. Jacobsen (ORCID: https://orcid.org/0000-0002-6033-9984)
- Falk Hillmann (ORCID: https://orcid.org/0000-0002-5493-930X)
- Axel A. Brakhage (ORCID: https://orcid.org/0000-0002-8814-4193)
- Franziska Hoffmann (ORCID: https://orcid.org/0000-0002-6872-924X)
- Alexander Iliou (ORCID: https://orcid.org/0009-0007-0263-3257)
- Michal Flak (ORCID: https://orcid.org/0000-0001-9869-8811)
- Silke Machata
- Ferdinand von Eggeling (ORCID: https://orcid.org/0000-0002-8062-6999)
- Zaher M. Fattal
Institutions
- University of Hohenheim (DE)
- Wismar University of Applied Sciences (DE)
- Medizinische Hochschule Hannover (DE)
- Helmholtz Centre for Infection Research (DE)
- German Center for Lung Research (DE)
- Jena University Hospital (DE)
- Leibniz-Institut für Naturstoff-Forschung und Infektionsbiologie e. V. - Hans-Knöll-Institut (HKI) (DE)
- Friedrich Schiller University Jena (DE)
Publication Details
- Journal
- EMBO Reports
- Published
- 2025-07-04
- DOI
- https://doi.org/10.1038/s44319-025-00508-3
- Citations
- 1
- Primary Topic
- Antifungal resistance and susceptibility
- Type
- article
- Field-Weighted Citation Impact
- 1.40
Funders
- Deutsche Forschungsgemeinschaft
- Bundesministerium für Bildung und Forschung