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Kinetic isotope effects in the oxidation of arachidonic acid by soybean lipoxygenase-1.

ABSTRACT: The reaction of soybean lipoxygenase-1 with linoleic acid has been extensively studied and displays very large kinetic isotope effects. In this work, substrate and solvent kinetic isotope effects as well as the viscosity dependence of the oxidation of arachidonic acid were investigated. The hydrogen atom abstraction step was rate-determining at all temperatures, but was partially masked by a viscosity-dependent step at ambient temperatures. The observed KIEs on k(cat) were large ( approximately 100 at 25 degrees C).

SUBMITTER: Jacquot C

PROVIDER: S-EPMC2652760 | biostudies-literature | 2008 Nov

REPOSITORIES: biostudies-literature

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Kinetic isotope effects in the oxidation of arachidonic acid by soybean lipoxygenase-1.

Jacquot Cyril C Peng Sheng S van der Donk Wilfred A WA

Bioorganic & medicinal chemistry letters 20080831 22

The reaction of soybean lipoxygenase-1 with linoleic acid has been extensively studied and displays very large kinetic isotope effects. In this work, substrate and solvent kinetic isotope effects as well as the viscosity dependence of the oxidation of arachidonic acid were investigated. The hydrogen atom abstraction step was rate-determining at all temperatures, but was partially masked by a viscosity-dependent step at ambient temperatures. The observed KIEs on k(cat) were large ( approximately ...[more]

PMID: 18793849

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