Methods of improving Trichoderma reesei as a whole cell biocatalyst

Abstract

Trichoderma reesei is a lamentous ascomycot with a very high potential to produce cellulases and hemicellulases, which gives it great importance in various biotechnological applications. It also makes the fungus capable of degrading complex lignocellulosic substrates, which makes it attractive for usage as whole cell biocatalyst, utilizing cheap and sustainable biowaste material as starting material. One focus of this work was to investigate the possibility of producing the arti cial sweetener erythritol in T. reesei, using wheat straw, pretreated by an alkaline organosolve process, as substrate. Therefore, rst the producing enzyme erythrose reductase was identi ed and characterized, and then an overexpression strains from the wild-type as well as from the mutant strain Rut-C30 was constructed in order to enhance production. A second aspect of improving the usability of T. reesei as a whole cell catalyst was to generally gain new insights in gene regulation by improving the in vivo footprinting technique in a way that even condition-dependent dierences in the methylateability of cis sites become visible. Therefore, the conduction of the analysis was improved, and additionally, a program that provides the necessary data evaluation, called ivFAST, was written.