Sigler K, Knotková A, Páca J, Wurst M
Folia Microbiol (Praha). 1980;25(4):311-7. doi: 10.1007/BF02876611.
Extrusion of metabolites (glycerol, lactic, malic, and succinic acid) during the medium acidification caused by resting baker's yeast supplied with 200 mM glucose was studied under aerobic and anaerobic conditions and in the absence and presence of 14 mM KCl. The maximum levels of glycerol and of the sum of acids (about 13 and 8 mM, respectively) were attained anaerobically; aerobiosis reduced the levels by 40-50% and the presence of K+ ions by another 10-20%. The time courses of glucose consumption and medium acidification were similar aerobically and anaerobically. The glucose consumption curves exhibited a short plateau about 2 min after glucose addition, caused probably by a rapid osmotic equilibration of glucose across the cell mambrane. Metabolite extrusion indicates that at high glucose concentrations the alcohol dehydrogenase reaction is supplemented by other reactions aiding in the maintenance of a balanced NAD+/NADH ratio in the cells.
在有氧和无氧条件下，以及在不存在和存在14 mM KCl的情况下，研究了在添加200 mM葡萄糖的静止面包酵母引起培养基酸化过程中代谢物（甘油、乳酸、苹果酸和琥珀酸）的分泌情况。厌氧条件下甘油和酸总和的最高水平分别达到约13 mM和8 mM；有氧条件使这些水平降低40 - 50%，而K⁺离子的存在又使其再降低10 - 20%。有氧和无氧条件下葡萄糖消耗和培养基酸化的时间进程相似。葡萄糖消耗曲线在添加葡萄糖后约2分钟出现一个短暂的平稳期，这可能是由于葡萄糖在细胞膜上快速渗透平衡所致。代谢物分泌表明，在高葡萄糖浓度下，酒精脱氢酶反应由其他有助于维持细胞内NAD⁺/NADH平衡的反应所补充。
