Effect of potassium and sodium ions on the cytoplasmic pH of an alkalophilic Bacillus
Effect of potassium and sodium ions on the cytoplasmic pH of an alkalophilic Bacillus
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钾和钠离子对嗜碱芽孢杆菌细胞质 pH 值的影响
DOI：
10.1016/0005-2736(85)90540-1
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发表时间：
1985
期刊：
影响因子：
--
通讯作者：
Y. Nosoh
中科院分区：
文献类型：
--
作者：
N. Koyama;Y. Nosoh
芽孢杆菌一种细菌，暂时命名为兼性嗜碱芽孢杆菌，在pH 7.5-10.2(Koyama，N.，Takinishi，H.和Nosoh，Y.(1983)FEMS Microbiol)中生长最好。让我们来吧。16213-216)。在pH低于8的范围内，KCl存在时，细菌的内部pH高于外部pH，但在pH高于9的范围内，无论有无KCl存在，细菌的内部pH都低于外部pH。因此，在外部pH为7.5~10.0的范围内，细菌在KCl存在下的内部pH可保持在8.2~9.2。在pH为7.5时，观察到H+以比交换K+的方式排出。在抗坏血酸和四甲基苯二胺的共同作用下，膜小泡表现出跨膜pH梯度(酸，内部)的形成，在氯化钠存在的情况下，随着囊外pH增加到8以上，这个梯度的幅度变大。通过H~+与K~+和Na~+的专性交换使细胞质发生碱化和酸化，以维持该菌的pH动态平衡。
A bacterium belonging toBacillusand tentatively designated as a facultatively alkalophilicBacillusgrows optimally at pH 7.5–10.2 (Koyama, N., Takinishi, H. and Nosoh, Y. (1983) FEMS Microbiol. Lett. 16 213–216). The internal pH of the bacterium was higher than the external pH in the pH range below 8, in the presence of KCl, but in the pH range above 9 the internal pH was lower than the external pH, both in the absence and presence of KCl. The internal pH of the bacterium in the presence of KCl was thus kept at 8.2–9.2 in the external pH range from 7.5 to 10.0. At pH 7.5, an extrusion of H+in specific exchange for K+was observed. The membrane vesicles, when energized with ascorbate plus tetramethylphenylenediamine, exhibited the formation of a transmembrane pH gradient (acid, interior), the magnitude of which became greater on increasing the extravesicular pH above 8 in the presence of NaCl. The alkalinization and acidification of the cytoplasm by the specific exchange of H+for K+and Na+, respectively, were suggested for a pH homeostasis of this bacterium.