title: Protoplast fusion of Schizosaccharomyces pombe Auxotrophic mutants of identical mating-type.
abstract: Protoplasts of methionine- and lysine-requiring h- mutants isolated from the L972 h- strain of Schizosaccharomyces pombe were fused. The protoplasts were obtained from the cells with enzymes produced by Trichoderma viride. When a mixture of the protoplasts was treated with 30% PEG 4000 solution containing 10 mM CaCl2, cell fusion and complementation was attained with a frequency of 0.17%. Both fusion partners were recovered among the spores after crossing of the fusion products with  the strain M210 ade6 h+. Cytological and haploidization examinations showed that the fusion cells are not heterokaryons, and that the increased amount of genetic material is situated in one nucleus.
mesh_terms: D001203:Ascomycota; D002459:Cell Fusion; D003227:Conjugation, Genetic; D005144:F Factor; D008715:Methionine / Q000378:metabolism; D009154:Mutation; D010641:Phenotype; D011523:Protoplasts; D012568:Schizosaccharomyces; D014443:Tyrosine / Q000378:metabolism
chemical_list: D014443:Tyrosine; D008715:Methionine