Enrichment technique for the selection of catabolite repression-resistant mutants of Trichoderma as producers of cellulase

Abstract The enrichment technique for the preparation of catabolite repression-resistant producers of cellulase from Trichoderma reesei is based on the submerged cultivation of mutagenized conidia on 2% (w/v) cellobiose or carboxymethyl-cellulose and in the presence of 0.5% (w/v) 2-deoxyglucose as the catabolite repressor. Conidia that are resistant towards the catabolite repressor can produce enzymes necessary for hydrolysis of used substrates and grow under the given conditions. They can be separated from the ungerminated conidia by filtration and used for the production of new conidia which are already enriched with catabolite repression-resistant mutants.