Pribylova Lenka, de Montigny Jacky, Sychrova Hana
Department of Membrane Transport, Institute of Physiology AS CR, 142 20 Prague 4, Czech Republic.
Yeast. 2007 Mar;24(3):171-80. doi: 10.1002/yea.1470.
The yeast Zygosaccharomyces rouxii is known for its high tolerance to osmotic stress, which is thought to be caused by sets of specific genes. Relatively few Z. rouxii genes have been identified so far, all of them having homologues in Saccharomyces cerevisiae; none of them was Z. rouxii-specific. Most of the known Z. rouxii genes were isolated from two wild-type strains, ATCC 2623 and ATCC 42981. In this study, we compared these two strains with regard to some of their morphological, physiological and genomic properties. Important differences were found in their salt tolerance and assimilation of glycerol and karyotype; slight differences were also present in their cell morphology. The ATCC 42981 strain showed a higher resistance to salts, higher glycerol production and, unlike ATCC 2623, was able to assimilate glycerol. Under conditions of osmotic stress, the glycerol production in both Z. rouxii strains was much lower than in a S. cerevisiae S288c culture, which suggested the presence of a system that efficiently retains glycerol inside Z. rouxii cells. The karyotype analysis revealed that ATCC 42981 cells contain more chromosomes and have a bigger genome size than those of ATCC 2623.
鲁氏接合酵母以其对渗透胁迫的高耐受性而闻名，这种耐受性被认为是由特定的基因组合引起的。到目前为止，已鉴定出的鲁氏接合酵母基因相对较少，所有这些基因在酿酒酵母中都有同源物；没有一个是鲁氏接合酵母特有的。大多数已知的鲁氏接合酵母基因是从两个野生型菌株ATCC 2623和ATCC 42981中分离出来的。在本研究中，我们比较了这两个菌株的一些形态、生理和基因组特性。发现它们在耐盐性、甘油同化和核型方面存在重要差异；在细胞形态上也存在细微差异。ATCC 42981菌株对盐的耐受性更高，甘油产量更高，并且与ATCC 2623不同，它能够同化甘油。在渗透胁迫条件下，两种鲁氏接合酵母菌株中的甘油产量都远低于酿酒酵母S288c培养物中的甘油产量，这表明鲁氏接合酵母细胞内存在一个能有效保留甘油的系统。核型分析表明，ATCC 42981细胞比ATCC 2623细胞含有更多的染色体，基因组更大。
