• Archives of Pharmacal Research
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• v.23 no.1
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• pp.79-86
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• 2000

Heterokaryotic nuclear hybrids overcoming the natural barriers of incompatibility have been studied in basidiomycetes. To produce these nuclear hybrids between incompatible mushrooms, which have several potent pharmacological effects, nuclear transfer was performed between Lentinula edodes and Coriolus versicolor. Nuclei from serine auxotrophs of Lentinula edodes, $LE207(Ser^{-})$ were transferred into the protoplasts of arginine auxotrophs of Coriolus versicolor, $CV17(Ser^{-})$using 30% polyethylene glycol 4000 in 10 mM $Cacl_{2}$-glycine solution (pH 8.0). Nulcear transfer progenies were selected by nutritional complementation on minimal media supplemented with 0.6 M sucrose. The progenies were classified based on colony morphology to L. edodes-like, C, versicolor-like and non-parental type. Most of the progenies grew slower than either parent. The number of nuclei per cell was similar but the DNA content varied between progenies. The isozyme patterns of nuclear hybrids resembled either of the parent porfiles or showed a mixed profile.

• Journal of Aquaculture
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• v.9 no.2
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• pp.133-140
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• 1996

Hybird and allotriploid between female rainbow trout (Oncorhynchus mykiss) and male coho salmon (O. kisutch) were produced by artificial fertilization and heat shocks. Hatching and survival rate of allotriploid at 2 month after hatching was $77.6\%$ and $54.5\%$ respectively, and these rates clearly exceeded those of their hybrid. Cell and nuclear sizes of the erythrocyte of hybrid were intermidiate of their parents and those of allotriploid were larger than thier hybird. The somatic chromosome number of viable hybrid was 2n = 60 and that of allotriploid was $90\~93$ with chromosomal polymorphism. Allotriploid karyotpe was constituted by two sets of rainbow trout chromosome and one set of coho salmon chromosome.

• Microbiology and Biotechnology Letters
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• v.24 no.1
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• pp.50-58
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• 1996

Interspecific hybrids between Aspergillus oryzae var oryzae and A. nidulans 514 were obtained by nuclear transfer technique. Several autotrophic mutants isolated from conidiospores of the two strains were mutagenized with ultraviolet and N-methyl-N-nitrosoguanidine. Optimal conditions for formation of intergeneric hybrids were investigated. Frequencies of hybrid formation by nuclear transfer were $3{\times}10^{-5}{\sim}1{\times}10^{-5}$. From observation of genetic stability, conidial size, DNA content, and nuclear stain, it was suggested that their karyptypes are aneuploid. The hybrids showed 1.1~1.4 fold higher xylanase activities than parental strains did. The xylanase of Aspergiilus sp. TAVD514-3 was purified and some of it's enzymatc characteristics were investigated. The enzyme was purified about 85 fold with an overall yield of 17% from the culture medium by ammonium sulfate fractionation, Sephadex G-75 gel permeation chromatography, and CM-sephadex A-50 ion exchange chromatography. The purified enzyme functions optimally at pH 9.0 and 80$^{\circ}C$. The enzymatic activity was increased by the presence of $Mg^{2+}$ and $Mn^2$ ions.