The generation of value-added products by conversion of non-food plant biomass is considered one of the most important tasks to achieve a sustainable bioeconomy. One strategy is to valorize industrial residuals and side-streams derived from plant biomass. Here, we aim to apply a microbial bioprocess to generate platform chemicals from biomass components. More specifically, pectin-rich biomass side-streams should be degraded to fermentable sugars by enzymatic conversion. Concurrently, these sugars should be converted to the platform chemical itaconic acid. Both steps will be integrated in a consolidated process using the plant pathogenic fungus Ustilago maydis as a whole-cell biocatalyst.
Strains will be optimized for degradation of pectin-rich biomass by the artificial activation of multiple intrinsic pectinolytic enzymes in the yeast phase. Itaconic acid production will also be enhanced by strain engineering. In parallel, we will establish the methodology for the growth of this fungus on viscous and complex substrates and up-scale the process to the fermenter level.
Impact on bioeconomy
A key aspect of bioeconomy is the conversion of plant biomass to bio-based products in order to replace fossil energy resources like petroleum. To reach this goal it is mandatory to avoid competition with plant biomass used for nutrition. One important strategy is the valorization of plant residuals that do not have nutritional value anymore. This is advantageous because it avoids costs for the disposal of the plant residuals and side-streams and moreover gives additional value to these residuals.
In the Boost Fund PectiLyse we will optimize the intrinsic potential of the plant pathogen Ustilago maydis for the production of the platform chemical itaconic acid using pectin-rich pulp that accumulates as a side-stream from the sugar beet industry.
Expected results/ project products
The PectiLyse project aims on the optimization of the fungus U. maydis for the simultaneous degradation of pectin-rich plant biomass and production of itaconic acid. Therefore, the intrinsic pectin-degrading activity of the fungus is activated by genetic engineering. To enhance the efficiency of the process, enzyme secretion is boosted by different strategies like deletion of protease encoding genes, manipulation of the secretory machinery and laboratory evolution. In parallel, cultivation of U. maydis on viscous substrates is established and optimized in small and large scale. Optimized strains will be fed with pectin-rich biomass accumulating as industrial wastes to evaluate the potential for industrial application.
Participating Core Groups
Dr. K. Schipper and Prof. Dr. M. Feldbrügge, Institute for Microbiology, HHU Düsseldorf
Dr. N. Wierckx and Prof. Dr. L. M. Blank, Institute of Applied Microbiology, RWTH Aachen University
Dr. T. Schlepütz and Prof. Dr.-Ing. J. Büchs, Aachener Verfahrenstechnik, RWTH Aachen University
Industrial partner: Pfeifer & Langen GmbH Co. KG, 50835 Köln
Dr. K. Schipper
Institute for Microbiology
Heinrich-Heine University Düsseldorf
Building 26.12.01 Room 64
01.11.2015 – 31.10.2017
The total budget of PectiLyse is € 441.327,00. PectiLyse is part of the NRW-Strategieprojekt BioSC and thus funded by the Ministry of Innovation, Science and Research of the German State of North Rhine-Westphalia.
Geiser, E, Ludwig, F, Zambanini, T, Wierckx, N and Blank, LM (2016). Draft genome sequences of itaconate-producing ustilaginaceae. Genome Announc 4(6).