12-Lipoxygenase from rat basophilic leukemia cells, an oxygenase with leukotriene A4-synthase activity.

Abstract

Rat basophilic leukemia cells exhibit 12-lipoxygenase activity only upon cell disruption. 12-Lipoxygenase may also possess 15-lipoxygenase activity, as is indicated by the formation of low amounts of 15(S)-HETE, in addition to the predominant product 12(S)-HETE, upon incubation of partially purified 12-lipoxygenase with arachidonic acid. With 5(S)-HPETE as substrate not only 5(S), 12(S)-diHETE and 5(S), 15(S)-diHETE are formed, but also LTA4, as was indicated by the presence of LTA4-derived LTB4-isomers. 12-Lipoxygenase from rat basophilic leukemia cells has many features in common with 12-lipoxygenase from bovine leukocytes. As was suggested for the latter enzyme, 12-lipoxygenase from rat basophilic leukemia cells may represent the remaining LTA4-synthase activity of 5-lipoxygenase, of which the 5-dioxygenase activity has disappeared upon cell disruption. Such a possible shift from 5-lipoxygenase activity to 12-lipoxygenase activity could not simply be induced by interaction of cytosolic 5-lipoxygenase with a membrane fraction after cell disruption, but may involve release of membrane-associated 5-lipoxygenase upon disruption of activated rat basophilic leukemia cells.

• Authors: E M van der Donk, J M Vervaart, J Verhagen, G A Veldink, J F Vliegenthart
• Journal: Biochimica et biophysica acta (Biochim Biophys Acta) Vol. 1128 Issue 1 Pg. 14-25 (Sep 22 1992) ISSN: 0006-3002 [Print] Netherlands
• PMID: 1390874 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• Hydroxyeicosatetraenoic Acids
• 5-hydroxy-6,8,11,14-eicosatetraenoic acid
• 15-hydroxy-5,8,11,13-eicosatetraenoic acid
• Arachidonate 12-Lipoxygenase
• Arachidonate 5-Lipoxygenase

Topics

• Animals
• Arachidonate 12-Lipoxygenase (isolation & purification, metabolism)
• Arachidonate 5-Lipoxygenase (isolation & purification, metabolism)
• Cell Fractionation
• Chromatography, High Pressure Liquid
• Cytosol (enzymology)
• Hydroxyeicosatetraenoic Acids (isolation & purification, metabolism)
• Kinetics
• Leukemia, Basophilic, Acute (enzymology)
• Rats
• Tumor Cells, Cultured