Intraspecific Hybridization of Trichoderma reesei by Protoplast Fusion

概要

論文の詳細を見る
Protoplasts ofbtained from mycelia of a single auxotrophic mutant of Trichodema reesei QM 9414 were fused with hose of T. reesei QM 9136 in the presence of 0.5 M glycine-NaOH buffer, pH 7.5,containing 0.05 M CaCl_2・2H_2O and 35% polyethylene glycol 4,000. The regeneration frequency of these protoplasts was 8.9-12.0% on a solid culture medium with soft agar overlay. The fused protoplasts successfully formed heterokaryons showing 3.33% of the fusion frequency. A heterozygous diploid was obtained from conidia of the heterokaryon by treatment with 0.1% d-camphor. The diploid showed a 1.9 fold DNA content per conidial nucleus compared to T. reesei QM 9414. The frequency of diploid formation was about 1.9×10^<-4> per conidium. Cellulase activities, such as filter paper degrading and CM-cellulose and Avicel saccharifying activities, and the xylanase activity of the diploid showed intermediate values between those of T. reesei QM 9414 and T. reesei QM 9136. However, the β-glucosidase, β-1,3-glucanase and chitinase activities of the diploid increased to levels equal to on above hose of T. reesei QM 9414 and T. reesei QM 9136. The existence of a parasexual cycle of T. reesei and the possibility of its application to enhanced enzyme productivity were confirmed using the protoplast fusion technique.
社団法人日本生物工学会の論文
1989-03-25