Cellulase Formation by Species ofTrichodermasect.Longibrachiatumand ofHypocreaspp. with Anamorphs Referable toTrichodermasect.Longibrachiatum

• Published in: Fungal genetics and biology 1996-06, Vol.20 (2), p.105-114
• Main Authors: Kubicek, Christian P., Bölzlbauer, Ulrike M., Kovacs, Werner, Mach, Robert L., Kuhls, Katrin, Lieckfeldt, Elke, Börner, Thomas, Samuels, Gary J.
• Format: Article
• Language: English
• Subjects: cellobiohydrolase; cellulase; Hypocrea; RFLP; Trichoderma; Trichoderma reesei
• ISSN: 1087-1845; 1096-0937
• DOI: 10.1006/fgbi.1996.0025

Kubicek, C. P., Bölzlbauer, U.M., Kovacs, W., Mach, R. L., Kuhls, K., Lieckfeldt, E., Börner, T., and Samuels, G. J. 1996. Cellulase formation by species ofTrichodermasect.Longibrachiatumand ofHypocreaspp. with anamorphs referable toTrichodermasect.Longibrachiatum. Fungal Genetics and Biology20,105–114. The cellulolytic potential of the wild-type strain ofTrichoderma reeseiwas compared to other members ofTrichodermasect.LongibrachiatumandHypocreaspp. that have anamorphs referable to that section. There was high diversity even within the same species (as defined by morphological and macromolecular characters). Differences, where notable, were more pronounced for carboxymethyl-cellulase activity than for filter paper activity. High cellulase activities were observed for several strains ofT. longibrachiatumandT. citrinoviride,whereasT. parceramosumformed only low levels of activity. Among the corresponding teleomorphs, most strains ofH. schweinitziiwere comparatively poor producers, whereas the highest percentage of high producers was found amongH. jecorinaisolates, and many strains were even more active than the parentT. reeseiQM 6a. Immunoblot analysis of corresponding culture filtrates of variousH. jecorinastrains showed that the three major cellulase proteins (cellobiohydrolase I, cellobiohydrolase II, and endoglucanase I) were present in culture filtrates and theirMrwas identical to that of the respectiveT. reeseiproteins. ELISA analysis demonstrated that these enzymes were also present in the same relative proportions in culture filtrates fromH. jecorinaandT. reesei.With the aid of primers, corresponding to conserved sequences in the cellobiohydrolase I-encoding genecbh1,a fragment of this gene was amplified from selected strains ofH. jecorina, T. reesei, T. longibrachiatum, T. citrinoviride,andH. schweinitzii.The fragments had the same size in all fungi. Cleavage of this fragment withHhaI produced a RFLP pattern which was identical inH. jecorinaandT. reesei,but different in the other species. In the latter, the RFLP pattern was also species specific. These results provide support for a close genetic similarity ofT. reeseiandH. jecorinacellulases. In the latter, an ascomycetous model system for cellulase biosynthesis is now availabale. The results further indicate that other anamorphs ofTrichodermasectionLongibrachiatumare promising sources of high cellulase production.