Zaldívar M, Steiner J, Musalem M, Contreras I
Departamento de Bioquímica y Biología Molecular, Facultad de Ciencas Químicas y Farmacéuticas, Universidad de Chile, Santiago.
Microbiologia. 1987 Feb;3(1):33-44.
The present study describes the production of cellulases by a native strain of Trichoderma pseudokoningii in the presence and absence of a catabolic repressor. We report a plate assay for selecting fungal mutants capable of synthesizing the cellulase enzymes under conditions of catabolite repression. This method was used for the selection of catabolite repression-resistant mutants. One mutant, B-1, secreted 3.3 times the extracellular protein and 3 times the endoglucanase and filter paper activity in submerged cultures when compared with the wild type strain. The cellobiase activity remained at similar levels in both strains. Although this mutant was isolated as i cellulase producer in the presence of 500 mM glycerol on agar plates, in liquid medium containing the repressor B-1 it exhibits only partial derepression of the cellulase complex.
本研究描述了在有和没有分解代谢阻遏物的情况下，里氏木霉天然菌株产生纤维素酶的情况。我们报告了一种平板测定法，用于选择在分解代谢阻遏条件下能够合成纤维素酶的真菌突变体。该方法用于选择抗分解代谢阻遏的突变体。与野生型菌株相比，一个突变体B-1在深层培养中分泌的细胞外蛋白是其3.3倍，内切葡聚糖酶和滤纸活性是其3倍。两种菌株的纤维二糖酶活性保持在相似水平。尽管该突变体是在琼脂平板上500 mM甘油存在的情况下作为纤维素酶产生菌分离得到的，但在含有阻遏物B-1的液体培养基中，它仅表现出纤维素酶复合物的部分去阻遏作用。
