A Tryptophanyl-tRNA Synthetase/tRNA Pair for Unnatural Amino Acid Mutagenesis in E. coli


  • We would like to acknowledge Virginia Seely for assistance in manuscript preparation and Dr. Xin Zhang for help in spectrum analysis. We thank Sophie Sun and Dr. Jenny Furman for fruitful discussions. This is paper 23000 from The Scripps Research Institute. This work is supported by grant DE-FG03-00ER46051 from the Division of Materials Sciences, Department of Energy (P.G.S.).


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Selected: A tryptophanyl-tRNA synthetase(TrpRS)/tRNA pair was evolved to genetically encode tryptophan analogues and other unnatural amino acids with large side chains in E. coli. A selection scheme was employed to identify TrpRS variants able to selectively charge tRNACUATrp with Trp analogues (see picture). Substitution of Trp66 in enhanced cyan fluorescent protein (ECFP) with these Trp analogues afforded ECFP variants with novel spectral properties.