OSMOTIC SIGNIFICANCE OF GLYCEROL ACCUMULATION IN EXPONENTIALLY GROWING YEASTS
OSMOTIC SIGNIFICANCE OF GLYCEROL ACCUMULATION IN EXPONENTIALLY GROWING YEASTS
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DOI：
10.1128/aem.53.9.2119-2123.1987
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发表时间：
1987-09-01
影响因子：
4.4
通讯作者：
GADD, GM
中科院分区：
文献类型：
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作者：
REED, RH;CHUDEK, JA;GADD, GM
天然丰度 13C 核磁共振波谱显示，在呈指数增长的盐胁迫的酿酒酵母、鲁氏接合酵母和汉逊德巴利酵母的细胞中，甘油是主要的具有渗透显着性的低分子量溶质。使用Boyle-van''t Hoff关系（对于非膨胀细胞，渗透体积与外部渗透压的倒数成正比）测量细胞内非渗透体积（即渗透无反应的细胞的分数）表明，非渗透体积高达细胞总体积的53%；最高值记录在添加最大 NaCl 的介质中。细胞内甘油水平相对于细胞渗透体积的测定表明，细胞内甘油的增加可以抵消由于添加的 NaCl 导致的高达 95% 的外部渗透压。 13C-核磁共振谱中缺乏其他有机渗透剂，表明无机离子可能构成细胞内渗透压的剩余成分。
Natural-abundance 13C-nuclear magnetic resonance spectroscopy has shown glycerol to be the major osmotically significant low-molecular-weight solute in exponentially growing, salt-stressed cells of the yeasts Saccharomyces cerevisiae, Zygosaccharomyces rouxii, and Debaryomyces hansenii. Measurement of the intracellular nonosmotic volume (i.e., the fraction of the cell that is osmotically unresponsive) by using the Boyle-van''t Hoff relationship (for nonturgid cells, the osmotic volume is directly proportional to the reciprocal of the external osmotic pressure) showed that the nonosmotic volume represented up to 53% of the total cell volume; the highest values were recorded in media with maximum added NaCl. Determinations of intracellular glycerol levels with respect to cell osmotic volumes showed that increases in intracellular glycerol may counterbalance up to 95% of the external osmotic pressure due to added NaCl. The lack of other organic osmotica in 13C-nuclear magnetic resonance spectra indicates that inorganic ions may constitute the remaining component of intracellular osmotic pressure.