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Updated: Jul 2, 2026

Quantification of the Abundance and Charging Levels of Transfer RNAs in Escherichia coli
Published on: August 22, 2017
T7 RNA polymerase transcription of Escherichia coli isoacceptors tRNA(Leu)
Abstract:
The T7 promoter and the gene encoding tRNA(Leu) were synthesized chemically and cloned into plasmid pUC19, where the gene was transcribed in vitro with T7 RNA polymerase purified. It was found that spermidine had a negative effect on T7 transcription. The amount of transcribed tRNA was about 250 times that of the template DNA under optimal reaction conditions. The unmodified tRNA(1) (Leu) and tRNA(2) (Leu) had similar leucine accepting ability, which however was only one fourth that of the native modified ones. This result indicated that the modified nucleotides of tRNA(Leu) played some though not key roles in its aminoacylation.
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