arachidonate 5-lipoxygenase activity Reactome:REACT_15337 leukotriene-A4 synthase activity EC:1.13.11.34 Reactome:REACT_99738 leukotriene-A(4) synthase activity Reactome:REACT_84894 arachidonic 5-lipoxygenase activity Reactome:REACT_15453 Reactome:REACT_84095 Reactome:REACT_102776 Reactome:REACT_28749 Reactome:REACT_80928 5-lipoxygenase activity Reactome:REACT_109247 Reactome:REACT_76963 GO:0004051 delta5-lipoxygenase activity MetaCyc:ARACHIDONATE-5-LIPOXYGENASE-RXN Catalysis of the reaction: arachidonate + O2 = (6E,8Z,11Z,14Z)-(5S)-5-hydroperoxycosa-6,8,11,14-tetraenoate. Reactome:REACT_101081 Reactome:REACT_113814 Reactome:REACT_78626 Reactome:REACT_110901 leukotriene A4 synthase LTA synthase activity Reactome:REACT_90210 delta(5)-lipoxygenase activity C-5-lipoxygenase activity Reactome:REACT_104725 RHEA:24751 5Delta-lipoxygenase activity Reactome:REACT_87806 Reactome:REACT_115370 5-delta-lipoxygenase activity arachidonate:oxygen 5-oxidoreductase activity Reactome:REACT_107991 molecular_function Reactome:REACT_79548 arachidonic acid 5-lipoxygenase activity Reactome:REACT_107795 Reactome:REACT_77245 oxidoreductase activity, acting on single donors with incorporation of molecular oxygen, incorporation of two atoms of oxygen