Functional consequences of T-stem mutations in E. coli tRNA^Thr_UGU in vitro and in vivo

Relationship between cell viability and ΔG° of binding to EF-Tu for tRNA^Thr variants. Boxes indicate the base pairs that were changed to create each variant. Bar height indicates the ΔG° of binding (Table 1), and bar color indicates the effectiveness of each variant in replacing the inactivated tRNA^Thr_UGU chromosomal gene. Green are fully functional variants where cells spontaneously lose pMAK705. Yellow are moderately functional variants where cells do not need pMAK705 to grow, but do not lose it spontaneously. Red are nonfunctional variants that do not grow without pMAK705 (see text and Fig. 3).