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Predicate | Object |
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rdf:type | |
lifeskim:mentions | |
pubmed:issue |
4
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pubmed:dateCreated |
1984-7-11
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pubmed:abstractText |
The steps of UUC recognition by tRNAPhe were analysed by temperature-jump measurements. At ion concentrations close to physiological conditions we found three relaxation processes, which we assigned to (1) formation of codon-anticodon complexes, (2) a conformational change of the anticodon loop coupled with Mg2+ binding, and (3) codon-induced association of tRNA. The relaxation data were evaluated both by the usual procedure (fitting the exponentials evaluated from the individual experiments of a set to a reaction model) and by "global fitting", i.e. fitting a set of relaxation curves obtained at various concentrations directly to a reaction model, thus leaving out the intermediate exponential fitting step. The data can be represented quantitatively by a three-step model: the codon binds to the anticodon at a rate of 4 X 10(6) to 6 X 10(6) M-1S-1 as is usual for the formation of oligomer helices; the conformation change of the anticodon loop is associated with inner sphere complexation of Mg2+ at a rate of 10(3) S-1; the codon-tRNA complexes form dimers at a rate of 5 X 10(6) to 15 X 10(6) M-1S-1. A similar mechanism is found for the binding of the wobble codon UUU to tRNAPhe at increased concentrations of Mg2+. Measurements at different Mg2+ concentrations demonstrate the distinct role of this ion in the codon recognition and the codon-induced tRNA dimerization. We propose a simple mechanism, based upon the special properties of magnesium ions, for long-distance transfer of reaction signals along nucleic acid chains.
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pubmed:language |
eng
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pubmed:journal | |
pubmed:citationSubset |
IM
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pubmed:chemical |
http://linkedlifedata.com/resource/pubmed/chemical/Anticodon,
http://linkedlifedata.com/resource/pubmed/chemical/Codon,
http://linkedlifedata.com/resource/pubmed/chemical/Magnesium,
http://linkedlifedata.com/resource/pubmed/chemical/RNA, Messenger,
http://linkedlifedata.com/resource/pubmed/chemical/RNA, Transfer, Amino Acyl,
http://linkedlifedata.com/resource/pubmed/chemical/tRNA, phenylalanine-
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pubmed:status |
MEDLINE
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pubmed:month |
Apr
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pubmed:issn |
0022-2836
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pubmed:author | |
pubmed:issnType |
Print
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pubmed:day |
25
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pubmed:volume |
174
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pubmed:owner |
NLM
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pubmed:authorsComplete |
Y
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pubmed:pagination |
587-604
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pubmed:dateRevised |
2000-12-18
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pubmed:meshHeading |
pubmed-meshheading:6563090-Anticodon,
pubmed-meshheading:6563090-Codon,
pubmed-meshheading:6563090-Kinetics,
pubmed-meshheading:6563090-Magnesium,
pubmed-meshheading:6563090-Models, Genetic,
pubmed-meshheading:6563090-Nucleic Acid Conformation,
pubmed-meshheading:6563090-RNA, Messenger,
pubmed-meshheading:6563090-RNA, Transfer, Amino Acyl,
pubmed-meshheading:6563090-Software,
pubmed-meshheading:6563090-Temperature
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pubmed:year |
1984
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pubmed:articleTitle |
Mechanism of codon recognition by transfer RNA and codon-induced tRNA association.
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pubmed:publicationType |
Journal Article
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