Perkins J, Gadd G M
Department of Biological Sciences, University of Dundee, UK.
FEMS Microbiol Lett. 1993 Mar 1;107(2-3):255-60. doi: 10.1111/j.1574-6968.1993.tb06039.x.
Accumulation of Li+ in Saccharomyces cerevisiae X2180-1B occurred via an apparent stoichiometric relationship of 1:1 (K+/Li+) when S. cerevisiae was incubated in the presence of 5 and 10 mM LiCl for 3 h. Other cellular cations (Mg2+, Ca2+ and Na+) did not vary on Li+ accumulation, although lithium chemistry dictates a degree of similarity to Group I and II metal cations. Compartmentation of Li+ was mainly in the vacuole which accounted for 85% of the Li+ accumulated after a 6-h incubation period. The remainder was located in the cytosol with negligible amounts being bound to cell fragments including the cell wall. Transmission electron microscopy of Li(+)-loaded cells revealed enlarged vacuoles compared with control cells. This asymmetric cellular distribution may therefore enhance tolerance of S. cerevisiae to Li+ and ensure that essential metabolic processes in the cytosol are not disrupted.
当酿酒酵母在5 mM和10 mM LiCl存在的条件下孵育3小时时，酿酒酵母X2180 - 1B中Li⁺的积累通过明显的1:1（K⁺/Li⁺）化学计量关系发生。其他细胞阳离子（Mg²⁺、Ca²⁺和Na⁺）在Li⁺积累时没有变化，尽管锂化学性质表明它与第I族和第II族金属阳离子有一定程度的相似性。Li⁺的区室化主要在液泡中，在6小时的孵育期后，液泡占积累的Li⁺的85%。其余的位于细胞质中，与包括细胞壁在内的细胞碎片结合的量可以忽略不计。与对照细胞相比，Li⁺负载细胞的透射电子显微镜显示液泡增大。因此，这种不对称的细胞分布可能会增强酿酒酵母对Li⁺的耐受性，并确保细胞质中的基本代谢过程不被破坏。
