Effect of mutation of potassium-efflux system, kefA on mechanosensitive channels in the cytoplasmic membrane of Escherichia coli
Effect of mutation of potassium-efflux system, kefA on mechanosensitive channels in the cytoplasmic membrane of Escherichia coli
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DOI：
10.1007/s002329900039
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发表时间：
1996-03-01
影响因子：
2.4
通讯作者：
Adler, J
中科院分区：
文献类型：
--
作者：
Cui, C;Adler, J
通过P1转导将kefA基因突变引入野生型大肠杆菌，建立了kefA突变对大肠杆菌细胞质膜机械敏感通道的影响。kefA基因的突变不仅使细胞对培养基中的K+敏感，而且改变了机械敏感通道的活性。kefA突变未改变大肠杆菌胞质膜上两个机械敏感通道的电导，但延长了通道的开放时间。此外，与野生型细胞相比，kefA突变使细胞对压力更敏感。kefA突变体对压力的高敏感性不受甜菜碱或跨膜钾梯度的调节。kefA突变对机械敏感通道的影响不是由于膜流动性的改变。KefA可能是机械敏感通道的调节器。
The effect of a kefA mutation on the mechanosensitive channels in the cytoplasmic membrane of Escherichia coli was established by introducing a muta tion of the kefA gene into wild-type E. coli by P1 transduction. The mutation of the kefA gene not only made the cells sensitive to K+ in the medium but also changed the mechanosensitive channel activity. The kefA mutation did not change the conductances of the two mechanosensitive channels in the cytoplasmic membrane of E. coli, but it prolonged the channel open time. Also, the kefA mutation made the cells more sensitive to pressure in comparison to wild-type cells. The high sensitivity to pressure of the kefA mutant was not modulated by betaine or by the potassium gradient across the membrane. The effect of the kefA mutation on mechanosensitive channels was not due to a membrane fluidity change. KefA might be a regulator for mechanosensitive channels.