Kopelowitz J, Schoulaker-Schwarz R, Lebanon A, Engelberg-Kulka H
Mol Gen Genet. 1984;196(3):541-5. doi: 10.1007/BF00436207.
We constructed plasmid pAtrp46 in which lacZ gene expression is regulated by the attenuator of the Escherichia coli tryptophan (trp) operon. The attenuation of trp, which occurs in the presence of an excess of tryptophan, is reflected by a decrease in the expression of the lacZ gene of pAtrp46 in a trpR- strain. Experiments with pAtrp46 further support our previous results (Engelberg-Kulka et al. 1982b) that suppression of a UGA termination codon by normal charged tRNATrp, a process called UGA readthrough, is a necessary mechanism in trp attenuation. Our experiments also suggest that plasmid pAtrp46 is useful for studies of other aspects of trp attenuation.
我们构建了质粒pAtrp46，其中lacZ基因的表达受大肠杆菌色氨酸（trp）操纵子衰减子的调控。在色氨酸过量存在时发生的trp衰减，通过trpR-菌株中pAtrp46的lacZ基因表达降低得以体现。用pAtrp46进行的实验进一步支持了我们之前的结果（Engelberg-Kulka等人，1982b），即正常带电荷的tRNATrp对UGA终止密码子的抑制作用（一个称为UGA通读的过程）是trp衰减中的必要机制。我们的实验还表明，质粒pAtrp46可用于trp衰减其他方面的研究。
