Figure 2. Effect of non-cognate amino acids on the growth of editing deficient E. coli strains.
Growth of E. coli pheT(G318W) strain (grey bars) relative to wild type (black bars) under increasing concentrations of L-p-Tyr (A) or D,L-m-Tyr (B) relative to Phe. Cultures were grown in M9 minimal media supplemented with amino acids expressed as a ratio of Phe:Tyr. A ratio of 1:1 corresponds to 3 µM of each amino acid. (C) Growth of PheRS editing deficient strain of E. coli in an MG1655 background in the presence of different tyrosine isomers at 37°C. Bars are the mean of three independent cultures, with errors bars representing ± SD.
Figure 2—figure supplement 1. EcPheRS post–transfer editing of mischarged tRNAPhe substrates.
Hydrolysis of 0.1 µM E. coli p-Tyr-[32P]-tRNAPhe (dashed lines) or m-Tyr-[32P]-tRNAPhe (solid lines) in the presence of 10 nM wild type EcPheRS (■) G318W EcPheRS (=) or buffer (▲) at 37°C. Data points are the mean of three independent experiments, with errors bars representing ± SD.
Figure 2—figure supplement 2. E. coli PheRS editing requirement for tyrosine isomers.
Growth of PheRS editing deficient E. coli at 37°C after 16 hr in M9 minimal media supplemented with increasing concentrations of (A) o-Tyr or (B) L-dopa. (C) Aminoacylation of [32P]-tRNAPhe with o-Tyr (=) or L-dopa (■) by E. coli G318W PheRS (1 µM). Bars are the mean of three independent cultures, with errors bars representing ± SD.