Key Findings

The study identifies several ribosomal protection protein (RPP) genes, including tet(M), tet(O), tet(W), tet(Q), tetB(P), and otr(A), that can confer high-level tetracycline resistance in E. coli. However, expression of these genes often comes with fitness costs, and certain mutations in tRNA genes (argW and proL) or the hns gene can mitigate these costs.