Summary
A hybrid of Saccharomyces diastaticus x Hansenula capsulate was obtained by conversion of the S. diastaticus parent to a petite, protoplasting and fusion of the strains and isolation of the hybrids on selective media, containing glycerol or galactose. All of the single-cell clones obtained resembled S. diastaticus in morphology, and fermented glucose, galactose, maltose, sucrose and starch. The hybrid sporulated, producing spores resembling those of S. diastaticus, but in asci which differed somewhat morphologically. The stability of the hybrid depended on the composition of the maintenance media, as hybrid clones maintained on glycerol medium lost their ability to sporulate after a few transfers and the cellular morphology altered to a form more closely resembling H. capsulate, and those maintained on glucose-containing medium lost the ability to utilize glycerol. Cultures maintained on yeast extract-starch medium retained the ability to sporulate and utilize glycerol. However, dissection of asci from the hybrid yielded clones, some of which had lost the ability to metabolize glycerol but which still sporulated. These clones had an unaltered cytochxome spectrum, and in other ways appeared to be respiratory competent. Washed cells of hybrids grown on galactose or starch as sole carbon source metabolized starch, as shown by respirometric measurements, but cells maintained on glycerol as sole carbon source had lost this ability. There was some evidence that the addition of vitamins stimulated oxygen uptake on starch by the hybrids. The formation of sporulating hybrids in the cross may permit the genetic analysis of other Saccharomyces x Hansenula crosses.
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Broock MR de van, Sierra M, Figueroa L de (1981) In: Stewart GG, Russell I (eds) Intergeneric fusion of yeast protoplasts. Current Developments in Yeast Research. Pergamon Press, Toronto, pp 171–176
Johnston JR, Mortimer RK (1959) Use of snail digestive juice in isolation of yeast spore tetrads. J Bacteriol 78:292
Kopp F (1975) Electron microscopy of yeasts. In Prescott DM (ed) Methods in Cell Biology Academic Press, New York London, pp 23–44
Lodder J, Kreger-van Rij NJW (1970) The Yeasts, a Taxonomic Study. North Holland Publishing Company, Amsterdam
Provost A, Bourguignon C, Fournier P, Ribet AM, Heslot H (1978) Intergeneric hybridization in yeasts through protoplast fusion. FEMS Letters 3:309–312
Sipiczki M (1979) Interspecific protoplast fusion in yeasts. Curr Microbiol 3:37–40
Spencer JFT, Spencer DM (1981) The use of mitochondrial mutants in hybridization of industrial yeasts. III. Restoration of mitochondrial function in petites of industrial yeast strains by fusion with respiratory-competent protoplasts of other yeast species. Curr Genet 4:177–180
Steer MW (1981) Understanding Cell Structure. Cambridge University Press, Cambridge
Weide LG, Clark MA, Rupert CS, Shay JW (1982) Detrimental effect of mitochondria on hybrid cell survival. Somatic Cell Genet 8:15–21
Whittaker PA, Leach SM (1978) Interspecific hybrid production between the yeast Kluyveromyces lactis and Kluyveromyces fragilis by protoplast fusion. FEMS Letts 4:31–34
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Spencer, J.F.T., Spencer, D.M., Whittington-Vaughan, P. et al. Use of mitochondrial mutants in the isolation of hybrids involving industrial yeast strains. Current Genetics 7, 159–164 (1983). https://doi.org/10.1007/BF00365642
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DOI: https://doi.org/10.1007/BF00365642