LaRiviere F J, Wolfson A D, Uhlenbeck O C
Department of Chemistry and Biochemistry, University of Colorado, Boulder, CO 80309-0215, USA.
Science. 2001 Oct 5;294(5540):165-8. doi: 10.1126/science.1064242.
Elongation factor Tu (EF-Tu) binds all elongator aminoacyl-transfer RNAs (aa-tRNAs) for delivery to the ribosome during protein synthesis. Here, we show that EF-Tu binds misacylated tRNAs over a much wider range of affinities than it binds the corresponding correctly acylated tRNAs, suggesting that the protein exhibits considerable specificity for both the amino acid side chain and the tRNA body. The thermodynamic contributions of the amino acid and the tRNA body to the overall binding affinity are independent of each other and compensate for one another when the tRNAs are correctly acylated. Because certain misacylated tRNAs bind EF-Tu significantly more strongly or weakly than cognate aa-tRNAs, EF-Tu may contribute to translational accuracy.
延伸因子Tu（EF-Tu）在蛋白质合成过程中结合所有延伸性氨酰基转移核糖核酸（aa-tRNA），以便将其递送至核糖体。在此，我们表明，与结合相应的正确酰化tRNA相比，EF-Tu以更广泛的亲和力范围结合错误酰化的tRNA，这表明该蛋白质对氨基酸侧链和tRNA主体均表现出相当高的特异性。氨基酸和tRNA主体对整体结合亲和力的热力学贡献彼此独立，并且当tRNA被正确酰化时相互补偿。由于某些错误酰化的tRNA与EF-Tu的结合比同源aa-tRNA显著更强或更弱，因此EF-Tu可能有助于提高翻译准确性。
