New colours for old in the blue-cheese fungus Penicillium roqueforti

Cleere, Matthew M.; Novodvorska, Michaela; Geib, Elena; Whittaker, Jack; Dalton, Heather; Salih, Nadhira; Hewitt, Sarah; Kokolski, Matthew; Brock, Matthias; Dyer, Paul S.

Abstract

Penicillium roqueforti is used worldwide in the production of blue-veined cheese. The blue-green colour derives from pigmented spores formed by fungal growth. Using a combination of bioinformatics, targeted gene deletions, and heterologous gene expression we discovered that pigment formation was due to a DHN-melanin biosynthesis pathway. Systematic deletion of pathway genes altered the arising spore colour, yielding white to yellow-green to red-pink-brown phenotypes, demonstrating the potential to generate new coloured strains. There was no consistent impact on mycophenolic acid production as a result of pathway interruption although levels of roquefortine C were altered in some deletants. Importantly, levels of methyl-ketones associated with blue-cheese flavour were not impacted. UV-induced colour mutants, allowed in food production, were then generated. A range of colours were obtained and certain phenotypes were successfully mapped to pathway gene mutations. Selected colour mutants were subsequently used in cheese production and generated expected new colourations with no elevated mycotoxins, offering the exciting prospect of use in future cheese manufacture.

Citation

Cleere, M. M., Novodvorska, M., Geib, E., Whittaker, J., Dalton, H., Salih, N., Hewitt, S., Kokolski, M., Brock, M., & Dyer, P. S. (2024). New colours for old in the blue-cheese fungus Penicillium roqueforti. npj Science of Food, 8(1), Article 3. https://doi.org/10.1038/s41538-023-00244-9

• Journal Article Type: Article
• Acceptance Date: Dec 18, 2023
• Online Publication Date: Jan 8, 2024
• Publication Date: Jan 8, 2024
• Deposit Date: Jun 20, 2025
• Publicly Available Date: Jun 23, 2025
• Journal: npj Science of Food
• Electronic ISSN: 2396-8370
• Publisher: Springer Nature
• Peer Reviewed: Peer Reviewed
• Volume: 8
• Issue: 1
• Article Number: 3
• DOI: https://doi.org/10.1038/s41538-023-00244-9
• Keywords: Public Health, Environmental and Occupational Health; Food Science
• Public URL: https://nottingham-repository.worktribe.com/output/29556918
• Publisher URL: https://www.nature.com/articles/s41538-023-00244-9#
• Additional Information: Received: 27 June 2023; Accepted: 18 December 2023; First Online: 8 January 2024; : One author (P.S.D.) is employed part-time and holds shares in the company Myconeos (ExternalRef removed), which holds a patent for cheese production using the A22 and B20 strains (International patent: PCT/EP2020/060793), but declares no financial competing interest. All other authors have no competing interests.