Importance of the G27‐A43 mismatch at the anticodon stem of Escherichia coli tRNAThr2

Abstract
The tRNAThr2 isoacceptor of E. coli has a G-A mismatch at positions 27–43. When the anticodon of this tRNA was converted to an amber anticodon (CUA), this tRNA showed suppressor activity in E. coli. Moreover, introduction of the base pair (G-C or U-A) at positions 27–43 of this suppressor tRNA reduced its suppressor activity. These results indicate that the G27-A43 mismatch is necessary for full function of tRNAThr2.