The lipid body lipoxygenase from cucumber seedlings exhibits unusual reaction specificity

FEBS Letters

Kühn, Hartmut²  Feussner, Ivo¹ 

[1] Institut für Pflanzenbiochemie, PO Box 250, Weinberg 3, D-06120 Halle, Germany;Institut für Biochemie, Universitätsklinikum Charité, Humboldt Universität Berlin, Hessische Str. 3-4, D-10115 Berlin, Germany

关键词: Cucumis sativus;    Lipid body;    Lipoxygenase;    Positional specificity;    Membrane binding;   

DOI  :  10.1016/0014-5793(95)00531-D

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

The lipid body lipoxygenase of cucumber seedlings is at a high level expressed during the germinating process which is the stage of triglyceride mobilisation. This enzyme exhibits an unusual positional specificity which has not been described so far for any plant and animal lipoxygenase. The purified enzyme converts arachidonic acid to 15-S-hydroperoxy-5Z,8Z,11Z, 13E-eicosatetraenoic acid (15S-HPETE), 12-S-hydroperoxy-5Z, 8Z, 10E, 14Z-eicosatetraenoic acid (12S-HPETE), and 8-S-hydroperoxy-5Z,9E,11Z,14Z-eicosatetraenoic acid (8S-HPETE) in a ratio of 76:4:20 with the corresponding R-isomers being only minor contaminants. Binding to the lipid bodies enhances the arachidonic acid dioxygenase activity more than 4-times and alters positional specificity of the enzyme in favour of 8-S-hydroperoxy-5Z,9E,11Z,14Z-eicosatetraenoic acid (8S-HPETE) formation.

【 授权许可】

Unknown