Shimizu Y, Shimizu N, Hayashi M
Proc Natl Acad Sci U S A. 1973 Jul;70(7):1990-4. doi: 10.1073/pnas.70.7.1990.
The in vitro repression of transcription of the tryptophan operon by the trp repressor from Escherichia coli was studied. By measuring the inhibitory effect for trp-specific RNA synthesis in an in vitro transcription system directed by DNA of trp-transducing phage, we have detected and concentrated a trp repressor in an eluate of a Phi80 ptED native DNA-cellulose column. The repression of transcription of trp operon required the addition of L-tryptophan in the system, and when several tryptophan analogues were added, the repression or derepression was similar to that observed in vivo. The repressor fraction was separated from the majority of tryptophanyl-tRNA synthetase activity by Bio-gel P60 column chromatography.
对来自大肠杆菌的色氨酸阻遏物在体外对色氨酸操纵子转录的抑制作用进行了研究。通过在由色氨酸转导噬菌体DNA指导的体外转录系统中测量对色氨酸特异性RNA合成的抑制作用,我们在Phi80 ptED天然DNA-纤维素柱的洗脱液中检测并浓缩了一种色氨酸阻遏物。色氨酸操纵子转录的抑制需要在系统中添加L-色氨酸,当添加几种色氨酸类似物时,抑制或去抑制情况与体内观察到的相似。通过Bio-gel P60柱色谱法将阻遏物组分与大部分色氨酰-tRNA合成酶活性分离。