Ion channels are likely to be involved in the two steps of phage T5 DNA penetration into Escherichia coli cells.
Ion channels are likely to be involved in the two steps of phage T5 DNA penetration into Escherichia coli cells.
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离子通道很可能参与噬菌体 T5 DNA 渗透到大肠杆菌细胞的两个步骤。
DOI：
10.1016/s0021-9258(19)50710-4
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发表时间：
1992
期刊：
影响因子：
--
通讯作者：
L. Letellier
中科院分区：
文献类型：
--
作者：
P. Boulanger;L. Letellier
T5噬菌体将其DNA分两步注入大肠杆菌细胞;首先注入8%的染色体，然后暂停，在此期间由该DNA片段编码的蛋白质被合成，从而允许剩余的DNA被注入。使用钾离子选择性电极，我们表明，注射的两个DNA片段与流出在两个步骤，细胞质钾。外排率与添加的噬菌体的数量线性相关，表明每个噬菌体诱导内膜中至少一个通道的形成。甚至在去极化细胞中也发生第一流出，这表明通道的插入和开放可以在没有质子的电化学梯度（Δ mu H+）的情况下发生。在合成噬菌体编码的蛋白质所需的时间内，通道处于闭合构型;这种闭合和第二次流出被细胞的去极化所阻止。将通道插入内膜中需要流体膜。结果表明，该通道的功能是转运噬菌体T5 DNA。
Phage T5 injects its DNA into Escherichia coli cells in two steps; 8% of the chromosome is first injected, and then there is a pause during which proteins encoded by this DNA fragment are synthesized allowing the remaining DNA to be injected. Using a potassium-selective electrode, we show that the injection of the two DNA fragments is associated with an efflux in two steps, of cytoplasmic potassium. The rate of efflux is linearly related to the number of added phages suggesting that each phage induces the formation of at least one channel in the inner membrane. The first efflux occurs even in depolarized cells suggesting that the insertion and the opening of the channel can take place in the absence of the electrochemical gradient of protons (delta mu H+). The channel is in a closed configuration during the time required for the synthesis of the phage-encoded proteins; this closing and the second efflux are prevented by the depolarization of the cell. The insertion of the channel in the inner membrane requires a fluid membrane. The results obtained suggest that the function of this channel is to translocate phage T5 DNA.