Direct mating between diploid sake strains of Saccharomyces cerevisiae |
| |
Authors: | Shinji Hashimoto Kazuo Aritomi Takafumi Minohara Yoshinori Nishizawa Hisashi Hoshida Susumu Kashiwagi Rinji Akada |
| |
Institution: | (1) Department of Applied Chemistry and Chemical Engineering, Faculty of Engineering, Yamaguchi University, Tokiwadai, Ube 755-8611, Japan;(2) Research and Development Department, Sanwa Kagaku Kenkyusho Co. Ltd., 363 Shiosaki, Hokusei, Inabe-shi Mie 511-0406, Japan;(3) Present address: Yamaguchi Prefectural Industrial Technology Institute, Asutopia, Ube 755-0151, Japan |
| |
Abstract: | Various auxotrophic mutants of diploid heterothallic Japanese sake strains of Saccharomyces cerevisiae were utilized for selecting mating-competent diploid isolates. The auxotrophic mutants were exposed to ultraviolet (UV) irradiation
and crossed with laboratory haploid tester strains carrying complementary auxotrophic markers. Zygotes were then selected
on minimal medium. Sake strains exhibiting a MATa or MATα mating type were easily obtained at high frequency without prior sporulation, suggesting that the UV irradiation induced
homozygosity at the MAT locus. Flow cytometric analysis of a hybrid showed a twofold higher DNA content than the sake diploid parent, consistent
with tetraploidy. By crossing strains of opposite mating type in all possible combinations, a number of hybrids were constructed.
Hybrids formed in crosses between traditional sake strains and between a natural nonhaploid isolate and traditional sake strains
displayed equivalent fermentation ability without any apparent defects and produced comparable or improved sake. Isolation
of mating-competent auxotrophic mutants directly from industrial yeast strains allows crossbreeding to construct polyploids
suitable for industrial use without dependence on sporulation. |
| |
Keywords: | |
本文献已被 PubMed SpringerLink 等数据库收录! |
|