Studies on arachidonate 5-lipoxygenase of rat basophilic leukemia cells.
Arachidonate 5-lipoxygenase was partially purified from rat basophilic leukemia cells with the aid of ATP as a ligand linked to Sepharose. The enzyme produced predominantly 5-hydroperoxy-6,8,11,14-eicosatetraenoic acid. Calcium ion was required for the enzyme activity (0.1 mM for half maximal activity), and the calcium-dependent reaction was stimulated by ATP and several nucleotides. 5,8,11,14,17-Eicosapentaenoic acid was converted to its 5-hydroperoxy derivative at a higher rate than arachidonate oxygenation. 5,8,11-Eicosatrienoic acid as substrate was almost as active as arachidonic acid. Among various lipoxygenase inhibitors tested, cirsiliol, a flavone derivative, was the most potent.
D000818:Animals; D001091:Arachidonate Lipoxygenases; D016718:Arachidonic Acid; D001095:Arachidonic Acids / Q000378:metabolism; D001491:Basophils / Q000201:enzymology; D002250:Carbon Radioisotopes; D007700:Kinetics; D007942:Leukemia, Experimental / Q000201:enzymology*; D019787:Linoleic Acid; D008041:Linoleic Acids / Q000378:metabolism; D008042:Linolenic Acids / Q000378:metabolism; D008084:Lipoxygenase / Q000378:metabolism*; D013058:Mass Spectrometry; D051381:Rats; D013379:Substrate Specificity; D017962:alpha-Linolenic Acid
D001095:Arachidonic Acids; D002250:Carbon Radioisotopes; D008041:Linoleic Acids; D008042:Linolenic Acids; D017962:alpha-Linolenic Acid; D016718:Arachidonic Acid; D019787:Linoleic Acid; D001091:Arachidonate Lipoxygenases; D008084:Lipoxygenase