LATERAL DIFFUSION OF PROTEINS IN THE PERIPLASM OF ESCHERICHIA-COLI
LATERAL DIFFUSION OF PROTEINS IN THE PERIPLASM OF ESCHERICHIA-COLI
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DOI：
10.1128/jb.165.3.787-795.1986
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发表时间：
1986-03-01
影响因子：
3.2
通讯作者：
GARLAND, PB
中科院分区：
文献类型：
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作者：
BRASS, JM;HIGGINS, CF;GARLAND, PB
我们已经引入了生物活性，荧光标记的麦芽糖结合蛋白到大肠杆菌的周质空间，并测量其横向扩散系数的荧光光漂白恢复方法。发现该蛋白质在周质中的扩散令人惊讶地低（横向扩散系数，0.9 × 104）。10-10 cm 2 s-1），比水介质中扩散的预期低约1，000倍，比细胞质中同等大小的蛋白质低近100倍。半乳糖结合蛋白，肌红蛋白，细胞色素c也被引入到周质中，并具有相同的麦芽糖结合蛋白确定的扩散系数。对于所有的蛋白质，几乎100%的荧光恢复后获得光漂白，表明周质是一个单一的连续隔室周围的细胞。这些数据有相当大的影响，周质结构和周质蛋白在运输和趋化性的作用。
We have introduced biologically active, fluorescently labeled maltose-binding protein into the periplasmic space of Escherichia coli and measured its lateral diffusion coefficient by the fluorescence photobleaching recovery method. Diffusion of this protein in the periplasm was found to be surprisingly low (lateral diffusion coefficient, 0.9 .times. 10-10 cm2 s-1), about 1,000-fold lower than would be expected for diffusion in aqueous medium and almost 100-fold lower than for an equivalent-size protein in the cytoplasm. Galactose-binding protein, myoglobin, and cytochrome c were also introduced into the periplasm and had diffusion coefficients identical to that determined for the maltose-binding protein. For all proteins nearly 100% recovery of fluorescence was obtained after photobleaching, indicating that the periplasm is a single continuous compartment surrounding the cell. These data have considerable implications for periplasmic structure and for the role of periplasmic proteins in transport and chemotaxis.