Interaction of elongation factor Tu with the aminoacyl transfer ribonucleic acid dimer Phe-tRNA-Glu-tRNA.
The effect of EF-Tu.GTP on the codon-anticodon interaction of AA-tRNA was studied by using as a model system the interaction of AA-tRNAs with complementary anticodons, namely, dimerization between yeast or Escherichia coli Phe-tRNAPhe (anticodon GmAA) and E. coli Glu-tRNAGlu (anticodon s2UUC) or nonacylated tRNAGlu in the presence or absence of EF-Tu.GTP. The present data indicate that the ternary complexes Phe-tRNA-EF-Tu.GTP and Glu-tRNA-EF-Tu.GTP can form dimers with a binding constant of (0.9 +/- 0.2) X 10(6) M-1, which is identical in magnitude with that of the dimer of the nonacylated tRNAs tRNAPhe-tRNAGlu and also with that of the complex Phe-tRNA-EF-Tu.GTP with nonacylated tRNAGlu. These results show that the anticodon region is not affected by complexation with EF-Tu.GTP; however, this conclusion does not preclude the possibility of structural changes in the anticodon loop that have no effect in energetic terms. In addition, this model codon-anticodon interaction does not stimulate hydrolysis of the GTP bound in the ternary complex.
D000926:Anticodon / Q000378:metabolism*; D001426:Bacterial Proteins / Q000378:metabolism*; D003062:Codon / Q000378:metabolism*; D004926:Escherichia coli / Q000378:metabolism; D006160:Guanosine Triphosphate / Q000378:metabolism; D007700:Kinetics; D010444:Peptide Elongation Factor Tu; D012333:RNA, Messenger / Q000378:metabolism*; D012343:RNA, Transfer / Q000378:metabolism*; D012346:RNA, Transfer, Amino Acyl / Q000378:metabolism*; D013050:Spectrometry, Fluorescence
D000926:Anticodon; D001426:Bacterial Proteins; D003062:Codon; D012333:RNA, Messenger; D012346:RNA, Transfer, Amino Acyl; C028850:tRNA, phenylalanine-tRNA, glutamic acid-; D006160:Guanosine Triphosphate; D012343:RNA, Transfer; D010444:Peptide Elongation Factor Tu