The modification landscape of P. aeruginosa tRNAs

RNA modifications have a substantial impact on tRNA function. While modifications in the anticodon loop play an important role in translational fidelity, modifications in the tRNA core influence tRNA structural stability. In bacteria, tRNA modifications play important roles in the stress response and expression of virulence factors. While tRNA modifications are well characterized in a few model organisms, our knowledge of tRNA modifications in human pathogens, such as Pseudomonas aeruginosa is lacking. Here we leveraged two orthogonal approaches to build a reference landscape of tRNA modifications in E. coli, which we used to identify tRNA modifications in P. aeruginosa. We determined conservation for many modifications between the two organisms. We also identified potential sites of tRNA modification in P. aeruginosa tRNA that are not present in E. coli. One of these sites is found at the same positions as acacp3U, a modification previously identified in Vibrio cholerae. Identifying which modifications are present on different tRNAs will uncover the pathways impacted by the different tRNA modifying enzymes, some of which may play roles in determining virulence and pathogenicity. Overall design: Illumina sequencing of purified RNA reverse transcribed using TGIRT and uniquely barcoded RT primers per each sample, RNA from bacteria grown in varying media conditions.