This thesis endorses the establishment of U. maydis as an alternative whole cell biocatalyst
for the biosynthesis of itaconate from renewable substrates such as cellulose or
hemicellulose. Therefore the fungal family Ustilaginaceae was screened for their natural
production of value added chemicals such as itaconate malate or succinate to identify
potential novel natural biocatalysts and to find the best producers. The screening was
facilitated by the development of a new medium composition (modified Tabuchi medium). In order
to combine the utilization of raw biomass components such as cellulose and hemicellulose with
the production of valuable platform chemicals such as itaconate the best itaconate producer
U. maydis MB215 was further characterized towards its xylan degradation ability and itaconate
production. A novel biosynthesis pathway for itaconate was identified including clustered
genes encoding the proteins responsible for itaconate production in U. maydis MB215. First
metabolic engineering attempts were already successful in enhancing U. maydis' itaconate
production two-fold by overexpressing the transcription factor regulating the expression of the
itaconate gene cluster. This work lays the foundation for further optimization of U. maydis'
itaconate biosynthesis and is therefore a further step towards industrial application of the
Ustilaginaceae for the advancement of a sustainable bio-based economy.
