Overproduction of tryptophanyl-tRNA synthetase relieves transcription termination at the Escherichia coli tryptophan operon attenuator.
نویسندگان
چکیده
Overproduction of tryptophanyl-tRNA synthetase increased trp operon expression by reducing transcription termination at the trp attenuator. The total cellular level of charged tRNATrp was not affected by increased levels of the synthetase. We propose that excess synthetase binds charged tRNATrp and reduces the concentration available for translation.
منابع مشابه
Regulation of tryptophan operon expression by attenuation in cell-free extracts of Escherichia coli.
Expression of the tryptophan (trp) operon of Escherichia coli was shown to be regulated by attenuation in an in vitro DNA-dependent protein-synthesizing system. In extracts prepared from a temperature-sensitive tryptophanyl-tRNA synthetase mutant, plasmid-directed trpE enzyme synthesis was inhibited 2- to 3-fold by addition of purified wild type tryptophanyl-tRNA synthetase. When the extract us...
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عنوان ژورنال:
- Journal of bacteriology
دوره 160 2 شماره
صفحات -
تاریخ انتشار 1984