Papiliotrema laurentii from two ecological niches: a possible source of next-generation photoprotective compounds

The transition toward a circular bioeconomy relies on identifying microorganisms with traits suitable for sustainable industry. This study explored the biotechnological potential of two Papiliotrema laurentii strains isolated from contrasting environments: urban São Paulo (FBU001) and the Atacama Desert (FBU003). The research focused on the safety profile of the strains, environmental stress resistance, and ability to produce photoprotective compounds. Taxonomic identity was confirmed through ribosomal DNA sequencing and MALDI-TOF Biotyper. Crucially, biosafety assessments, including growth temperature limits and the absence of common fungal virulence factors, combined with in vivo infection models, indicated that both strains have low pathogenic potential and are safe for industrial applications. Physiological tests showed that while both strains resist UVC radiation, the Atacama strain possesses additional extremophilic adaptations like osmotic stress tolerance. Both yeasts produced mycosporine-glutaminol (MG), a natural antioxidant and UV filter. Genomic and transcriptional analyses confirmed that the genes responsible for this compound are organized in a cluster (MYC BGC) activated by UV exposure, suggesting that MG production is a conserved trait in the species regardless of its habitat. These findings position these yeasts as robust candidates for sustainable biotechnology. By offering a bio-based alternative to synthetic sunscreen ingredients, this work supports the development of renewable, biodegradable cosmetics within a circular bioeconomy framework. Key points • P. laurentii from diverse geographic origin are avirulent and produce MG under UVR. • P. laurentii from the Atacama Desert are highly resistant to multiple stress factors. • MYC BGC transcription is UVR induced and it is associated with the production of MG.