5-Fluoro-2′-Deoxyuridylate: Covalent Complex with Thymidylate Synthetase
AUTOR(ES)
Santi, Daniel V.
RESUMO
5-Fluoro-2′-deoxyuridylate causes a rapid inactivation of thymidylate synthetase that is dependent upon prior complexation of the cofactor 5,10-methylenetetrahydrofolate. The enzyme-5-fluoro-2′-deoxyuridylate complex may be isolated on nitrocellulose membranes and is not disrupted by 6 M urea. Upon reaction of 5-fluoro-2′-deoxyuridylate with the enzyme in the presence of 5,10-methylenetetrahydrofolate a rapid loss of absorbance is observed at 269 nm, the absorption maximum for the pyrimidine chromophore. It is concluded that a covalent bond is formed between the 6-position of 5-fluoro-2′-deoxyuridylate and a nucleophilic group of the enzyme that is involved in catalysis.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=426818Documentos Relacionados
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