Cluzel P, Surette M, Leibler S
Department of Physics, Princeton University, Princeton, NJ 08544, USA.
Science. 2000 Mar 3;287(5458):1652-5. doi: 10.1126/science.287.5458.1652.
Understanding biology at the single-cell level requires simultaneous measurements of biochemical parameters and behavioral characteristics in individual cells. Here, the output of individual flagellar motors in Escherichia coli was measured as a function of the intracellular concentration of the chemotactic signaling protein. The concentration of this molecule, fused to green fluorescent protein, was monitored with fluorescence correlation spectroscopy. Motors from different bacteria exhibited an identical steep input-output relation, suggesting that they actively contribute to signal amplification in chemotaxis. This experimental approach can be extended to quantitative in vivo studies of other biochemical networks.
在单细胞水平上理解生物学需要同时测量单个细胞中的生化参数和行为特征。在此，测量了大肠杆菌中单个鞭毛马达的输出作为趋化信号蛋白细胞内浓度的函数。通过荧光相关光谱法监测与绿色荧光蛋白融合的该分子的浓度。来自不同细菌的马达表现出相同的陡峭输入-输出关系，表明它们在趋化作用中积极促进信号放大。这种实验方法可以扩展到其他生化网络的定量体内研究。
