Functional consequences of T-stem mutations in E. coli tRNAThrUGU in vitro and in vivo. Journal Article uri icon



  • The binding affinities between Escherichia coli EF-Tu and 34 single and double base-pair changes in the T stem of E. coli tRNA(Thr)(UGU) were compared with similar data obtained previously for several aa-tRNAs binding to Thermus thermophilus EF-Tu. With a single exception, the two proteins bound to mutations in three T-stem base pairs in a quantitatively identical manner. However, tRNA(Thr) differs from other tRNAs by also using its rare A52-C62 pair as a negative specificity determinant. Using a plasmid-based tRNA gene replacement strategy, we show that many of the tRNA(Thr)(UGU) T-stem changes are either unable to support growth of E. coli or are less effective than the wild-type sequence. Since the inviable T-stem sequences are often present in other E. coli tRNAs, it appears that T-stem sequences in each tRNA body have evolved to optimize function in a different way. Although mutations of tRNA(Thr) can substantially increase or decrease its affinity to EF-Tu, the observed affinities do not correlate with the growth phenotype of the mutations in any simple way. This may either reflect the different conditions used in the two assays or indicate that the T-stem mutants affect another step in the translation mechanism.

publication date

  • June 1, 2011

has subject area

has restriction

  • bronze

Date in CU Experts

  • March 13, 2015 12:56 PM

Full Author List

  • Saks ME; Sanderson LE; Choi DS; Crosby CM; Uhlenbeck OC

author count

  • 5

published in

  • RNA  Journal

Other Profiles

Electronic International Standard Serial Number (EISSN)

  • 1469-9001

Additional Document Info

start page

  • 1038

end page

  • 1047


  • 17


  • 6