Intraspecific Protoplast Fusion in Trichoderma koningii

Trichoderma koningii의 種間 原形質體 融合에 대한 硏究

  • Hong, Soon-Woo (Department of Microbiology, College of Natural Sciences, Seoul National University) ;
  • Hah, Yung-Chil (Department of Microbiology, College of Natural Sciences, Seoul National University) ;
  • Park, Hee-Moon (Department of Microbiology, College of Natural Sciences, Seoul National University) ;
  • Cho, Nam-Jin (Department of Microbiology, College of Natural Sciences, Seoul National University)
  • 홍순우 (서울大學校 自然科學大學 生活物理科) ;
  • 하영칠 (서울大學校 自然科學大學 生活物理科) ;
  • 박희문 (서울大學校 自然科學大學 生活物理科) ;
  • 조남진 (서울大學校 自然科學大學 生活物理科)
  • Published : 1984.01.01

Abstract

The conditions for the protoplast fusion of auxotrophic mutants of Trichoderma koningii were determined. A preparation of commercial enzyme Driselase was used successfully to isolate protoplasts from the 18 hr old mycelium of T. koningii. The yields of protoplasts production were ranged from $0.3{\times}10^8$ to $2.5{\times}10^8$ protoplasts per mg of damp mycelium of various auxotrophic mutant strains. The regeneration frequencies from $9.3{\times}10^{-3}\;to\;2.0{\times}10^{-1}$ were obtained when the protoplasts from auxotrophic mutants were plated on the malt extract medium containing 0.6M $MgSO_4$, and 2% agar, and the optimal concentration of PEG for protoplst fusion was 30%. Exposure of protoplasts to PEG for 10 min was found to be sufficient to induce high frequency heterokaryon formation. Optimal pH of fusion mixture was determined as 5.5, and 1 mM of calcium chloride in fusion mixture was found to be sufficient to enhance protoplast fusion frequency. Under optimal condition, the fusion frequency of the cross between protoplasts from various auxotrophic mutants were $1.6{\times}10^{-2}\;and\;4.1{\times}10^{-2}$.

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