title: Experimental evidence for kinetic proofreading in the aminoacylation of tRNA by synthetase.
abstract: The enzymatic aminoacylation of tRNA can be viewed as a means of proofreading either the amino acid or the tRNA or both. We have conducted further experimental tests of kinetic proofreading in  discriminating between cognate and noncognate amino acids and tRNAs as follows: (formula: see text). In cases (i) and (ii) the amino acids are proofread, in cases (iii) and (iv) the tRNA is proofread, and in case (v), both the amino acid and the tRNA are proofread. ATP consumed per acylation was 400, 1.5, 40, 25, and 1000, respectively. High ATP/aminoacylation ratios are diagnostic for kinetic proofreading.
mesh_terms: D000604:Amino Acyl-tRNA Synthetases / Q000378:metabolism*; D004926:Escherichia coli / Q000201:enzymology; D007533:Isoleucine-tRNA Ligase / Q000378:metabolism*; D007700:Kinetics; D009239:N-Formylmethionine; D010649:Phenylalanine; D012343:RNA, Transfer / Q000378:metabolism*; D046249:Transfer RNA Aminoacylation; D014448:Tyrosine-tRNA Ligase / Q000378:metabolism*; D014637:Valine-tRNA Ligase / Q000378:metabolism*
chemical_list: D009239:N-Formylmethionine; D010649:Phenylalanine; D012343:RNA, Transfer; D000604:Amino Acyl-tRNA Synthetases; D014448:Tyrosine-tRNA Ligase; D007533:Isoleucine-tRNA Ligase; D014637:Valine-tRNA Ligase