Kotyk A, Georghiou G
Institute of Physiology, Academy of Sciences of the Czech Republic, Prague.
Folia Microbiol (Praha). 1993;38(6):467-72. doi: 10.1007/BF02814397.
Effects of starvation and glucose preincubation on membrane potential, ATPase-mediated acidification and glutamic acid transport were studied in yeast species Saccharomyces cerevisiae, Schizosaccharomyces pombe, Dipodascus magnusii, Lodderomyces elongisporus and Rhodotorula gracilis. The membrane potential was highest after preincubation with glucose in all species but L. elongisporus and R. gracilis. In all cases the membranes were depolarized in the presence of 20 mmol/L KCl and hyperpolarized with 50 mumol/L diethylstilbestrol (DES). The extracellular acidification caused by addition of glucose was highest after preincubation with glucose in all cases except in R. gracilis where there was none. In all cases except in R. gracilis addition of KCl caused a marked increase in the acidification rate. Addition of DES with glucose caused a large decrease in rate in S. cerevisiae but had much less effect on the other species. Transport of glutamic acid was clearly increased after pretreatment with glucose in S. cerevisiae, S. pombe and D. magnusii (mainly due to enhanced synthesis of the carrier) but actually decreased in R. gracilis and L. elongisporus. Addition of DES had an inhibitory effect in all species but much more pronounced in S. cerevisiae and S. pombe than in others. In general, both the acidification and the transport of glutamate were enhanced after preincubation with glucose but much more so in the semianaerobic species, such as S. cerevisiae, than in the strict aerobes (R. gracilis) where the effect was occasionally negative. There was no relationship between the ATPase-mediated acidification and the membrane potential.
研究了饥饿和葡萄糖预孵育对酿酒酵母、粟酒裂殖酵母、大双孢酵母、长孢洛德酵母和纤细红酵母等酵母菌种膜电位、ATP酶介导的酸化作用以及谷氨酸转运的影响。除长孢洛德酵母和纤细红酵母外，所有菌种在葡萄糖预孵育后膜电位最高。在所有情况下，膜在20 mmol/L KCl存在时去极化，在50 μmol/L己烯雌酚（DES）作用下超极化。除纤细红酵母外，所有情况下葡萄糖预孵育后添加葡萄糖引起的细胞外酸化作用最高，而纤细红酵母中则无此现象。除纤细红酵母外，所有情况下添加KCl均导致酸化速率显著增加。葡萄糖与DES一起添加时，酿酒酵母的速率大幅下降，但对其他菌种的影响较小。在酿酒酵母、粟酒裂殖酵母和大双孢酵母中，葡萄糖预处理后谷氨酸转运明显增加（主要由于载体合成增强），但在纤细红酵母和长孢洛德酵母中实际上下降。添加DES对所有菌种均有抑制作用，但在酿酒酵母和粟酒裂殖酵母中比其他菌种更明显。一般来说，葡萄糖预孵育后酸化作用和谷氨酸转运均增强，但在半厌氧菌种如酿酒酵母中增强程度比严格需氧菌（纤细红酵母）更大，在严格需氧菌中这种影响偶尔为负。ATP酶介导的酸化作用与膜电位之间没有关系。
