Polykaryon formation using a swollen conidium of Trichoderma reesei

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Hideo Toyama1, Makiko Yano, Takeshi Hotta

  • 1Department of Health and Nutrition, Minamikyushu University, Kirishima 5-1-2, Miyazaki 880-0032, Japan. gaf00771@nifty.com

Applied Biochemistry and Biotechnology
|April 1, 2004
PubMed

Insights

This study demonstrates a novel method for generating polykaryons in Trichoderma reesei using swollen conidia and colchicine. This technique enables the selection of cellulase hyperproducers without compromising growth rate.

Area of Science:

  • Mycology
  • Biotechnology
  • Genetics

Background:

  • Trichoderma fungi possess oval, mononucleate conidia.
  • Conidia swell and become spherical in liquid media, increasing internal space.
  • This swelling facilitates the formation of larger autopolyploid nuclei.

Purpose of the Study:

  • To investigate polykaryon formation in swollen Trichoderma reesei conidia.
  • To develop a method for selecting improved cellulase-producing strains.
  • To explore autopolyploidization for enhanced fungal traits.

Main Methods:

  • Swelling of Trichoderma reesei QM6a conidia in Mandel's medium.
  • Autopolyploidization of swollen conidia using the mitotic arrester, colchicine.
  • Induction of polykaryon formation from autopolyploidized swollen conidia.

Main Results:

  • Autopolyploid nuclei were successfully generated in swollen conidia.
  • Multiple smaller nuclei, similar in size to original nuclei, formed from autopolyploid nuclei.
  • Polykaryon formation was achieved using swollen conidia.

Conclusions:

  • Swollen conidia offer a viable platform for autopolyploidization and polykaryon formation.
  • This method allows for the selection of cellulase hyperproducing Trichoderma strains.
  • The approach maintains growth rate while enhancing cellulase production.

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