Chorismate synthase. Pre-steady-state kinetics of phosphate release from 5-enolpyruvylshikimate 3-phosphate.
نویسندگان
چکیده
The pre-steady-state kinetics of phosphate formation from 5-enolpyruvylshikimate 3-phosphate catalysed by Escherichia coli chorismate synthase (EC 4.6.1.4) were studied by a rapid-acid-quench technique at 25 degrees C at pH 7.5. No pre-steady-state 'burst' or 'lag' phase was observed, showing that phosphate is released concomitant with the rate-limiting step of the enzyme. The implications of this result for the mechanism of action of chorismate synthase are discussed.
منابع مشابه
Site-Directed Mutagenesis, Expression and Biological Activity of E. coli 5-Enolpyruvylshikimate 3-Phosphate Synthase Gene
Site-directed mutagenesis (SDM) as a powerful technique was used to change two important and conserved amino acids in 5-enolpyruvylshikimate 3- phosphate synthase (EPSPS) gene of E. coli. The mutations changed glycine 96 to alanine and alanine 183 to threonine. These two amino acids are very important for intraction of the wide spectrum herbicide, glyphosate, to EPSP synthase enzymes. By design...
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Chorismate synthase catalyzes the 1,4-elimination of phosphate and the C-(6-pro-R) hydrogen from 5-enolpyruvylshikimate 3-phosphate (EPSP) to generate chorismate. Although this reaction does not involve an overall change in redox state, the enzyme requires reduced FMN. To investigate the role of the flavin in catalysis we have employed chemically modified flavins: 1- and 5-deaza-, 2- and 4-thio...
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Chorismate synthase catalyzes the conversion of 5-enolpyruvylshikimate 3-phosphate to chorismate in the shikimate pathway, which represents an attractive target for discovering antimicrobial agents and herbicides. Chorismate serves as a common precursor for the synthesis of aromatic amino acids and many aromatic compounds in microorganisms and plants. Chorismate synthase requires reduced FMN as...
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عنوان ژورنال:
- The Biochemical journal
دوره 265 3 شماره
صفحات -
تاریخ انتشار 1990