title: Lipoxin synthesis by arachidonate 12-lipoxygenase purified from porcine leukocytes.
abstract: Arachidonate 12-lipoxygenase purified from porcine leukocytes shows 14R-oxygenase and 14, 15-leukotriene A synthase activities with 15-hydroperoxy-arachidonic acid as substrate. The enzyme transformed 5, 15-dihydroperoxy-arachidonic acid to several compounds with a conjugated tetraene. A major product was identified as 5S, 14R, 15S-trihydroperoxy-6, 10, 12-trans-8-cis-eicosatetraenoic acid, which was reduced to 5S, 14R, 15S-8-cis-lipoxin B. A requirement of molecular oxygen and the results of H2(18)O experiments suggested that formation of the latter compound was attributed mostly to the 14R-oxygenase activity of the enzyme. There were several other minor products identified as lipoxin A and B isomers. They were produced presumably by hydrolysis of 14, 15-epoxy compound formed by the leukotriene A synthase activity of 12-lipoxygenase.
mesh_terms: D000818:Animals; D001092:Arachidonate 12-Lipoxygenase / Q000378:metabolism*; D001091:Arachidonate Lipoxygenases / Q000378:metabolism*; D016718:Arachidonic Acid; D001095:Arachidonic Acids / Q000378:metabolism*; D006893:Hydroxyeicosatetraenoic Acids / Q000096:biosynthesis*; D007962:Leukocytes / Q000201:enzymology*; D015289:Leukotrienes; D008054:Lipid Peroxides / Q000378:metabolism*; D044045:Lipoxins; D010100:Oxygen / Q000378:metabolism; D013552:Swine
chemical_list: D001095:Arachidonic Acids; D006893:Hydroxyeicosatetraenoic Acids; D015289:Leukotrienes; D008054:Lipid Peroxides; D044045:Lipoxins; D016718:Arachidonic Acid; C054539:5,15-dihydroperoxyeicosatetraenoic acid; C042651:lipoxin B4; D001091:Arachidonate Lipoxygenases; D001092:Arachidonate 12-Lipoxygenase; D010100:Oxygen