Abstract
Nineteen analogs of ATP have been tested in the aminoacylation of valyl-tRNA, isoleucyl tRNA and tyrosyl-tRNA synthetases from baker's yeast. Four compounds are substrates for valyl tRNA and two for isoleucyl-tRNA synthetase, but there is no modified substrate for the tyrosyl tRNA synthetase. There is one inhibitor for valyl-tRNA synthetase, eight compounds inhibit isoleucyl-tRNA synthetase and two compounds inhibit tyrosyl-tRNA synthetase. Their Km and Ki and V values have been determined. The substrate specificity shows that positions 2, 6, 7, 8, 9, 2', and 3' of ATP are important for catalytic action of these aminoacyl-tRNA synthetases.
MeSH terms
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Adenosine Triphosphate / analogs & derivatives*
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Amino Acyl-tRNA Synthetases / metabolism*
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Binding, Competitive
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Catalysis
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Chemical Phenomena
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Chemistry
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Isoleucine-tRNA Ligase / antagonists & inhibitors
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Isoleucine-tRNA Ligase / metabolism*
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Kinetics
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Saccharomyces cerevisiae / enzymology*
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Structure-Activity Relationship
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Transfer RNA Aminoacylation
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Tyrosine-tRNA Ligase / antagonists & inhibitors
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Tyrosine-tRNA Ligase / metabolism*
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Valine-tRNA Ligase / antagonists & inhibitors
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Valine-tRNA Ligase / metabolism*
Substances
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Adenosine Triphosphate
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Amino Acyl-tRNA Synthetases
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Tyrosine-tRNA Ligase
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Isoleucine-tRNA Ligase
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Valine-tRNA Ligase