TRANSFER OF MICRONUCLEI-LIKE STRUCTURE OF TRICHODERMA-REESEI QM-9414 INTO PROTOPLASTS OF SACCHAROMYCES-CEREVISIAE

Minute nuclei, i.e. the 'smaller nuclei', were generated when the myce lia of a cellulase producing fungus, Trichoderma reesei QM 9414, were incubated for over 24 h at 40 degrees C or 50 degrees C. The average D NA content of the isolated 'smaller nuclei' was about quarter of that of the isolated normal nuclei. This means that the 'smaller nuclei' ob tained here were not the nuclei condensed by higher temperature. When the normal nuclei were used for the karyoduction into protoplasts of S accharomyces cerevisiae, no yeast colonies which were capable of proli feration on the solid medium containing CMC-Na appeared after the rege neration. However, when the 'smaller nuclei' were used, the regenerate d colonies could grow on the solid medium containing CMC-Na. The 'smal ler nuclei' may be applicable for gene transfer in microbes.