Dokument: Compositional and Genomic Factors Underlying the Efficiency of Corn Stover Bioconversion by Ustilago maydis
| Titel: | Compositional and Genomic Factors Underlying the Efficiency of Corn Stover Bioconversion by Ustilago maydis | |||||||
| URL für Lesezeichen: | https://docserv.uni-duesseldorf.de/servlets/DocumentServlet?id=72639 | |||||||
| URN (NBN): | urn:nbn:de:hbz:061-20260325-170233-1 | |||||||
| Kollektion: | Dissertationen | |||||||
| Sprache: | Englisch | |||||||
| Dokumententyp: | Wissenschaftliche Abschlussarbeiten » Dissertation | |||||||
| Medientyp: | Text | |||||||
| Autor: | Robertz, Stefan Josef [Autor] | |||||||
| Dateien: |
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| Beitragende: | Prof. Dr. Pauly, Markus [Gutachter] Prof. Dr. Feldbrügge, Michael [Gutachter] | |||||||
| Dewey Dezimal-Klassifikation: | 500 Naturwissenschaften und Mathematik » 570 Biowissenschaften; Biologie | |||||||
| Beschreibung: | A key aspect of a sustainable bioeconomy is the bioconversion of renewable,
agricultural waste streams by microorganisms for the production of high-value compounds. A promising approach is the bioconversion of corn stover by the fungus Ustilago maydis. U. maydis is able to grow on corn stover as the sole nutrient source. However, the utilization of this abundant agricultural waste is often hindered by its complex and heterogeneous nature and the need for an efficient breakdown into a suitable feedstock. The specific corn stover components utilized by U. maydis and the bottlenecks in the fermentation process remain largely unexplored. To tackle this challenge, the first chapter of this thesis describes a platform to monitor U. maydis performance growing on corn stover. It uses online measurements of scattered light, fluorescence and pH to track fungal growth, combined with a detailed biochemical characterization of the post-fermentation biomass. The results reveal that U. maydis primarily feeds on the water-soluble carbohydrates present in corn stover, while the lignocellulosic fraction remains underutilized. To improve conversion of the abundant lignocellulosic fraction the effect on fungal performance of different lignocellulose corn mutants and different lignocellulose pretreatments was evaluated. The use of a lignin mutant (bm3) in combination with a commercial cellulolytic enzyme cocktail proofed to be the most efficient performance boost and combined, increased fungal performance by 120 % compared to wildtype corn stover (variety B73). The second chapter focuses on the water-soluble carbohydrate fraction in corn stover, which is the most influential on U. maydis biomass production. The results highlight the substantial variability of this important fraction across a corn natural variation panel. To identify the genetic basis of this variation, a genome wide association study was conducted, which identified 37 quantitative trait loci associated with water-soluble carbohydrate related traits. Haplotype-chemotype association studies identified three candidate genes potentially involved in corn stover water-soluble carbohydrate traits. Functional studies in Saccharomyces cerevisiae, Nicotiana benthamiana or in vitro validated the roles of two of the candidate genes and revealed haplotype-specific differences in protein activity for one candidate gene. These insights lay a foundation for further studies to increase water-soluble carbohydrate content in corn stover and thereby enhancing bioconversion by U. maydis. | |||||||
| Lizenz: |  Dieses Werk ist lizenziert unter einer Creative Commons Namensnennung 4.0 International Lizenz | |||||||
| Fachbereich / Einrichtung: | Mathematisch- Naturwissenschaftliche Fakultät » WE Biologie | |||||||
| Dokument erstellt am: | 25.03.2026 | |||||||
| Dateien geändert am: | 25.03.2026 | |||||||
| Promotionsantrag am: | 04.11.2025 | |||||||
| Datum der Promotion: | 05.03.2026 |
