CAREER: Friend or Foe: Investigating the Chemical Weapons Produced by the Bioherbicide Colletotrichum spinosum

The total global food demand is projected to increase significantly over the next couple of decades, yet plant diseases and invading species lead to considerable losses in global crop production. Although some species of fungi can cause plant diseases or produce harmful toxins that affect plants, humans, and the environment, other fungal species produce small molecules that help protect plants and humans by acting as fungicides or antibiotics. This project aims to investigate how the little-studied fungus Colletotrichum spinosum interacts with the “world’s worst weed” - the invasive plant Xanthium spinosum. Colletotrichum spinosum has the genetic potential to produce small molecules that might act as “chemical weapons” against certain plants, potentially acting as herbicides against weeds, but very little is known about these molecules. By identifying and studying these small molecules, this research will enhance our understanding of fungal-plant interactions and how small molecules are key to this interaction. The findings may lead to new ways of protecting crops from pests and diseases and will also contribute to the development of new biotechnological solutions for agriculture. Additionally, the project will provide valuable educational opportunities for undergraduate students, allowing them to participate in cutting-edge research and contribute to scientific discoveries. Through hands-on involvement in the research process, students will gain real-world experience, including collaborations with local artists to communicate the findings in engaging ways, that will help prepare them for future careers in science and technology. Overall, this research will advance scientific knowledge, foster innovation in biotechnology and artificial intelligence, support workforce development, while addressing important challenges in agriculture and environmental sustainability. Xanthium spinosum is an invasive noxious weed that affects essential crops such as corn, tomatoes, and sugar cane, and is difficult to contain. The fungus Colletotrichum spinosum has demonstrated ability to kill young Xanthium spinosum plants by an unknown mechanism. This project aims to identify and characterize the specialized metabolites produced by Colletotrichum spinosum and assess their role in the fungus’ interaction with the weed, such as being essential for pathogenicity, for example. The research will uncover previously unreported metabolites using genome mining, metabolomics, transcriptomics, comparative genomics, and heterologous expression in Aspergillus oryzae (a generally regarded as safe host). Once discovered, purified metabolites will be structurally elucidated using mass spectrometry and nuclear magnetic resonance techniques and tested for bioactivity against Xanthium spinosum and other plants to explore whether certain metabolites act independently of the fungal host. In parallel, a team of scientists at different career stages, will be trained to perform the research and disseminate results using traditional channels and more community-focused approaches. This research has the potential to uncover new antifungal or herbicidal compounds with applications in agriculture and plant protection. The project will also contribute to a broader understanding of fungal metabolic diversity and its ecological roles. Ultimately, it aims to provide valuable insights into how fungi adapt to their environments and could lead to new biotechnology strategies for invasive plant species and crop protection. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria. NSF Award ID: 2542819 | Program: 01002627DB NSF RESEARCH & RELATED ACTIVIT,01003031DB NSF RESEARCH & RELATED ACTIVIT | Principal Investigator: Elizabeth Skellam | Institution: University of North Texas, DENTON, TX | Award Amount: $909,256 View on NSF Award Search: https://www.nsf.gov/awardsearch/show-award/?AWD_ID=2542819 View on Research.gov: https://www.research.gov/awardapi-service/v1/awards/2542819.html