E. coli tRNA (NEB #N6845) is isolated from a B strain, different from MRE600 (K12 strain). However, codon frequency in B and K strains is very similar, and it correlates with relative tRNA abundance. Transcriptome-wide analysis of codon usage in E. coli demonstrates that there is low variability at the species level.
We have experimentally determined that the cell culture process and tRNA isolation method are critical to quality, while the E.coli source strain is not. The purification process for E.coli tRNA (NEB #N6845) ensures a complete tRNA population, as well as purity and absence of inhibitory contaminants.
