We assessed the ability of two strains of Escherichia coli, BL21 (DE3) and Tuner (DE3), to express a variant of the B1 domain of protein G, which forms a side-by-side dimer, by using fluorine-labeling and 19F nuclear magnetic resonance spectroscopy. BL21 cells express the protein in a binary, all-or-none, manner, where more cells express the protein at a high level with an increasing inducer concentration. Tuner cells express the protein in a rheostatic manner, where expression increases across all cells with an increasing inducer concentration.

中文翻译：

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使用调谐细胞对蛋白质表达进行变阻性控制。

通过使用氟标记和19F，我们评估了两种大肠杆菌BL21（DE3）和Tuner（DE3）菌株表达G蛋白B1结构域变体的能力，该蛋白形成并排的二聚体。核磁共振波谱学。BL21细胞以二元，全或无的方式表达蛋白质，其中随着诱导物浓度的增加，更多的细胞以高水平表达蛋白质。调谐细胞以变阻性的方式表达蛋白质，其中所有细胞的表达都随着诱导剂浓度的增加而增加。