Name des Kandidaten
Name der PrüferInnen
Jonas Ramoni, MSc
PD Dr. Bernhard Seiboth
Assoc.-Prof. Dr. Martina Marchetti-Deschmann
Prof. Dr. Ronald de Vries
“Novel players involved in biomass degradation in
Trichoderma reesei”
Trichoderma reesei is a paradigm for the regulation and production of plant cell wall degrading enzymes.
Several industries, most prominently biorefinery industries, uses its enzymes to saccharify lignocellulose
from renewable plant biomass in order to produce biobased fuels and chemicals. Although the increasing
availability of omics technologies has ushered into a new era in T. reesei research, functional genomics
studies and classic enzymatic characterization remain key to proof the functions of proteins and enzymes.
Here, we will present our work on the characterization of three players in lignocelluloses degradation.
Xylanase 5 is a GH11 xylanase which is produced in a truncated form in the academic and industrial strain
line of T. reesei. We could identify functional copies of this gene in other wild-type strains and show that
the replacement of the truncated form of xyn5 led to an improvement in overall xylanase activity.
Conflicting results were published on the involvement of swollenin in lignocelluloses degradation which
might be due to the production in a heterologous host or insufficient purification. We therefore
overexpressed the enzyme in a T. reesei cellulase free background. The results indicate that swollenin does
not have hydrolytic activity itself, but might be involved in assisting other (hemi)cellulases in efficient
degradation of biomass. Msb2, a transmembrane protein, is implicated in signaling of cellulose to the
fungus. This protein and its role in cellulase regulation was studied in this thesis.