+ Site Statistics
+ Search Articles
+ PDF Full Text Service
How our service works
Request PDF Full Text
+ Follow Us
Follow on Facebook
Follow on Twitter
Follow on LinkedIn
+ Subscribe to Site Feeds
Most Shared
PDF Full Text
+ Translate
+ Recently Requested

Hydrolytic action of aminoacyl-tRNA synthetases from baker's yeast. "Chemical proofreading" of Thr-tRNA Val by valyl-tRNA synthetase studied with modified tRNA Val and amino acid analogues

Hydrolytic action of aminoacyl-tRNA synthetases from baker's yeast. "Chemical proofreading" of Thr-tRNA Val by valyl-tRNA synthetase studied with modified tRNA Val and amino acid analogues

Biochemistry 16(8): 1696-1702

The properties of native and of two modified tRNA Val species in the correction of misactivated threonine by valyl-tRNA synthetase have been studied. Whereas Thr-tRNA Val-C-C-A could not be isolated in the valyl-tRNA synthetase catalyzed reaction, Thr-tRNA Val-C-C-3'dA is isolable in up to 50% yield in this system and tRNA Val-C-C-3'NH2A is fully aminoacylated with threonine by the same enzyme. The hydrolysis of preformed Thr-tRNA Val-C-C-A by free valyl-tRNA synthetase is 30 times faster than the corresponding breakdown of Val-tRNA Val-C-C-A. This hydrolytic activity is also observed with Thr-tRNA Val-C-C-3'dA although the rate is reduce to that of the reaction of Val-tRNA Val-C-C-A. Modification of the threonine to O-methylthreonine, which is also a substrate for valyl-tRNA synthetase, leads to stabilization of the O-methylthreonyl-tRNA esters. The AMP/PP independent hydrolysis under aminoacylating conditions, which is a measure of the correction process, indicates that O-MeThr-tRNA Val-C-C-A is only very slowly corrected while the tRNA Val-C-C-3'dA and tRNA Val-C-C-3'NH2A esters are completely stable. Removal of the methoxy group of O-methylthreonine as in alpha-amino-butyric acid increases the rate of the hydrolytic reaction and once again alpha-Abu-tRNA Val-C-C-A and alpha-Abu-tRNA Val-C-C-3'dA are unstable under aminoacylating conditions and not isolable.

Please choose payment method:

(PDF emailed within 1 workday: $29.90)

Accession: 040320697

Download citation: RISBibTeXText

PMID: 322705

Related references

Hydrolytic action of aminoacyl-tRna synthetases from baker's yeast. "Chemical proofreading" of Thr-tRna Val by valyl-tRna synthetase studied with modified tRna Val and amino acid analogs. Biochemistry 16(8): 1696-1702, 1977

Hydrolytic action of aminoacyl-tRNA synthetases from baker's yeast: "chemical proofreading" preventing acylation of tRNA(I1e) with misactivated valine. Biochemistry 15(18): 4131-4138, 1976

The plant aminoacyl-tRNA synthetases. Purification and characterization of valyl-tRNA, tryptophanyl-tRNA and seryl-tRNA synthetases from yellow-lupin seeds. European Journal of Biochemistry 52(2): 301-310, 1975

Phenylalanyl-tRNA synthetase from baker's yeast: role of 3'-terminal adenosine of tRNA-Phe in enzyme-substrate interaction studied with 3'-modified tRNA-Phe species. Proceedings of the National Academy of Sciences of the United States of America 72(4): 1378-1382, 1975

Aminoacyl-tRNA synthetases from yeast: generality of chemical proofreading in the prevention of misaminoacylation of tRNA. Biochemistry 17(17): 3459-3468, 1978

Valyl-tRNA, isoleucyl-tRNA and tyrosyl-tRNA synthetase from baker's yeast. Substrate specificity with regard to ATP analogs and mechanism of the aminoacylation reaction. European Journal of Biochemistry 66(3): 493-497, 1976

Threonyl-tRNA, lysyl-tRNA and arginyl-tRNA synthetases from Baker's yeast. Substrate specificity with regard to ATP analogues. European Journal of Biochemistry 84(2): 499-502, 1978

Fluorescence studies of the binding of valyl-tRNA synthetase and tryptamine to valine-specific tRNA. A possible role for tryptophan residues in the binding of aminoacyl-tRNA synthetases to tRNAs. Febs Letters 17(1): 73-77, 1971

Mechanism of aminoacylation of tRNA. Influence of spermine on the kinetics of aminoacyl-tRNA synthetases by isoleucyl- and valyl-tRNA synthetases from Mycobacterium smegmatis. Biochimica et Biophysica Acta 654(1): 94, 1981

The plant aminoacyl-tRNA synthetases. Effect of sodium chloride on tRNA aminoacylation and aminoacyl-tRNA decomposition catalysed by aminoacyl-tRNA synthetases from yellow lupin seeds. Acta Biochimica Polonica 24(2): 163-170, 1977

Valyl-tRNA synthetase from yeast. Discrimination between 20 amino acids in aminoacylation of tRNA(Val)-C-C-A and tRNA(Val)-C-C-A(3'NH2). European Journal of Biochemistry 191(1): 123-129, 1990

Valyl-tRNA synthetase gene of Escherichia coli K12. Primary structure and homology within a family of aminoacyl-TRNA synthetases. Journal of Biological Chemistry 263(2): 868-877, 1988

Purification of aminoacyl-tRNA synthetases by affinity chromatography on tRNA-sepharose columns. Application to rat liver seryl-tRNA synthetase. Biochimie 56(5): 625-630, 1974

Regulation of the biosynthesis of aminoacyl-tRNA synthetases and of tRNA in Escherichia coli. IV. Mutants with increased levels of leucyl- or seryl-tRNA synthetase. Molecular and General Genetics 169(2): 205-211, 1979

Human histidyl-tRNA synthetase: recognition of amino acid signature regions in class 2a aminoacyl-tRNA synthetases. Nucleic Acids Research 20(5): 1075-1081, 1992