Simultaneously catalyzes two reactions, namely formation of ethylene and of succinate from 2-oxoglutarate, with a molar ratio of 2:1. 2-oxoglutarate + 2 H(+) + O2 = 3 CO2 + ethene + H2O 2-oxoglutarate + L-arginine + O2 = (S)-1-pyrroline-5-carboxylate + CO2 + guanidine + H(+) + H2O + succinate Activated by catalase. Inhibited by chelating reagents such as EDTA and Tiron (4,5-dihydroxy-1,3-benzene disulphonic acid), and by DTNB (5,5'-dithio-bis-2-nitrobenzoate) and hydrogen peroxide. Optimum pH is 7.0-7.5. Optimum temperature is 20-25 degrees Celsius. Alkene biosynthesis; ethylene biosynthesis via 2-oxoglutarate. Monomer. A dual-circuit mechanism has been proposed in PubMed:1445291 for the complete reaction, in which the binding of L-arginine and 2-oxoglutarate in a Schiff-base structure generates a common intermediate for the two reactions. Belongs to the iron/ascorbate-dependent oxidoreductase family.