Seminar of the Department of Microbiology
MSc Student Session 5
Jäger Iris – MSc candidate – UIBK - E-Omics
Niccolò Mariani – MSc candidate – UIBK - Mycology
Tobias Schiff – MSc candidate – UIBK - Mycology
04.12.2025, 11:00
- Join online
- or in presence: Seminarraum Biologie - (Technikerstr. 25, Viktor-Franz-Hess Haus, Parterre)
Abstracts
Jäger: Exploring landfill leachate as a potential reservoir for plastic-degrading bacteria
Plastic pollution is a growing global concern, with increasing amounts of plastic waste ending up in landfills and the environment. Because of its durability, micro and nano-sized plastic particles persist in terrestrial and aquatic ecosystems for many decades. Therefore, there is a growing need to recover and recycle more plastic. An eco-friendly approach of plastic degradation could involve microbes that utilize plastic as a carbon source through specific enzymatic processes. The main goal of this study is to characterize the microbial community in landfill leachate from the retired landfill Graslboden in Tyrol, Austria. Landfill leachate provides an ideal reservoir for microorganisms to evolve under harsh and complex conditions, being rich in organic materials and chemicals. Such environments can favor microbial adaptation to plastic as a carbon source. Advanced metagenomic and transcriptomic analyses are used to characterize the microbial communities in the leachate and identify functional genes associated with plastic degradation. Additionally, enrichment cultures of the leachate with plastic as its sole carbon source are employed to explore plastic degradation and its capacity in a controlled environment under varying conditions. This approach offers the potential to discover novel bacterial candidates and enzymatic mechanisms that could contribute to sustainable plastic waste management in the future.
Mariani: Conditional Production and Growth Optimization of Photosensitizers in Talaromyces islandicus
Photodynamic therapy (PDT) depends on light-activated photosensitizers that generate reactive oxygen species to selectively kill cancer cells. Because new and more effective photosensitizers are needed, filamentous fungi are being explored as sources of photoactive secondary metabolites. Talaromyces islandicus produces several quinoid and anthraquinone pigments, including the potential photosensitizers iridoskyrin and islandicin. This thesis investigates how environmental and nutritional factors influence photosensitizer production in T. islandicus, with a particular focus on condition-dependent synthesis of iridoskyrin and islandicin. Fungal cultures grown on different conditions were analyzed by HPLC to compare metabolite profiles. Preliminary data suggests that (i) the growth medium strongly determines both biomass and metabolite composition, and (ii) iridoskyrin and islandicin are produced independently, suggesting more complex regulation than previously assumed. Current work aims to validate these findings and identify the conditions that consistently induce iridoskyrin and islandicin production. The most favourable conditions will then be scaled up to assess their potential for controlled bioprocess development.