Expanding the Genetic Code of Escherichia coli

@article{Wang2001ExpandingTG,
  title={Expanding the Genetic Code of Escherichia coli},
  author={Lei Wang and Ansgar Brock and Brad Herberich and Peter G. Schultz},
  journal={Science},
  year={2001},
  volume={292},
  pages={498 - 500}
}
A unique transfer RNA (tRNA)/aminoacyl-tRNA synthetase pair has been generated that expands the number of genetically encoded amino acids in Escherichia coli. When introduced into E. coli, this pair leads to the in vivo incorporation of the synthetic amino acid O-methyl-l-tyrosine into protein in response to an amber nonsense codon. The fidelity of translation is greater than 99%, as determined by analysis of dihydrofolate reductase containing the unnatural amino acid. This approach should… 
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Expanding the genetic code.
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TLDR
The feasibility of expanding the genetic code of Escherichia coli using its own tryptophanyl-tRNA synthetase and tRNA (TrpRS-tRNATrp) pair is demonstrated and a general strategy to develop additional aaRS- tRNA pairs that can be used for UAA mutagenesis of proteins expressed in both E. coli and eukaryotes is provided.
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