Cation Transport in Escherichia coli: V. Regulation of cation content.
Cation Transport in Escherichia coli: V. Regulation of cation content.
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DOI：
10.1085/jgp.49.2.221
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发表时间：
1965-11-01
期刊：
影响因子：
--
通讯作者：
Schultz SG
中科院分区：
文献类型：
--
作者：
Epstein W;Schultz SG
在生长的大肠杆菌中细胞K和Na浓度的测量表明，培养基的渗透压是细胞K浓度的主要决定因素。相比之下，细胞钠浓度与培养基渗透压无关，并且很大程度上取决于培养基的钠浓度。培养基渗透压摩尔浓度的突然变化导致K含量的快速变化。用较低渗透压的溶液洗涤细胞会导致K的快速损失，在更稀和更冷的溶液中损失更大。生长培养基渗透压浓度的突然增加通过一种机制产生K的快速吸收，该机制的速率是培养基中K浓度的饱和函数，并且似乎涉及K与细胞H的交换。
Measurement of cellular K and Na concentrations in growing Escherichia coli indicates that the osmololity of the medium is a major determinant of the cell K concentration. In contrast, the cell Na concentration is independent of the medium osmolality and is largely dependent on the Na concentration of the medium. Sudden changes in the osmolality of the medium lead to rapid changes in K content. Washing the cells with solutions of lower osmolality results in a very rapid loss of K, which is greater in more dilute and in cold solutions. A sudden increase in the osmolality of the growth medium produces a rapid uptake of K by a mechanism whose rate is a saturable function of the K concentration of the medium and which appears to involve an exchange of K for cellular H.