title: Porcine leukocyte 5- and 12-lipoxygenases are iron enzymes.
abstract: 5- and 12-lipoxygenases isolated from porcine leukocytes were investigated by electron paramagnetic resonance at X-band and atomic absorption spectroscopy. For comparison potato 5-lipoxygenase was studied under identical experimental conditions. All three lipoxygenases contained between 0.7 and 0.9 Fe atoms/enzyme molecule. As isolated, both mammalian enzymes exhibited a characteristic EPR signal at low magnetic field with a maximum at g = 5.20 indicative of a high-spin ferric iron center. The signal was not affected by the oxidants 12-hydroperoxyeicosatetraenoic acid or arachidonic acid, nor was it affected by the reductant nordihydroguaiaretic acid. In the case of the potato enzyme an intense EPR signal with resonances at g = 7.50, 6.39 and 5.84 was only observed after addition of an oxidant, such as 9-hydroperoxyoctadecadienoic acid.
authors.affiliation: Fakultät für Biologie, Universität Konstanz, Germany.
authors.forename: P M
authors.initials: PM
authors.lastname: Kroneck
authors.forename: C
authors.initials: C
authors.lastname: Cucurou
authors.forename: V
authors.initials: V
authors.lastname: Ullrich
authors.forename: N
authors.initials: N
authors.lastname: Ueda
authors.forename: H
authors.initials: H
authors.lastname: Suzuki
authors.forename: T
authors.initials: T
authors.lastname: Yoshimoto
authors.forename: S
authors.initials: S
authors.lastname: Matsuda
authors.forename: S
authors.initials: S
authors.lastname: Yamamoto
mesh_terms: D000818:Animals; D001092:Arachidonate 12-Lipoxygenase / Q000032:analysis* / Q000737:chemistry; D001094:Arachidonate 5-Lipoxygenase / Q000032:analysis* / Q000737:chemistry; D004578:Electron Spin Resonance Spectroscopy; D007501:Iron / Q000032:analysis*; D007962:Leukocytes / Q000201:enzymology*; D015289:Leukotrienes / Q000494:pharmacology; D008041:Linoleic Acids / Q000494:pharmacology; D016859:Lipoxygenase Inhibitors; D009637:Masoprocol / Q000494:pharmacology; D011198:Solanum tuberosum / Q000201:enzymology; D013025:Glycine max / Q000201:enzymology; D013552:Swine
chemical_list: D015289:Leukotrienes; D008041:Linoleic Acids; D016859:Lipoxygenase Inhibitors; C049606:9-hydroperoxy-11,12-octadecadienoic acid; C021201:12-HPETE; D009637:Masoprocol; D007501:Iron; D001092:Arachidonate 12-Lipoxygenase; D001094:Arachidonate 5-Lipoxygenase