Abstract:

The development of ethylene biosynthesis is essential. By screening ethylene forming enzyme (EFE) homologue genes in sev-eral microorganisms, an EFE protein with high activity from Neofusicoccumparvum(NpEFE) was identified. The heterogenous expression of this efegene in E.coliBL21(DE3) was successfully realized with pET28a as the vector and its enzymatic properties were analyzed. The specific activity of NpEFEwas(730.7±56.9)U /mgandtheoptimumpHforcatalysiswas7.5. Undertheactivityassayconditions, NpEFE exhibited a Km of 155.7μmol /L and a kcat of 51. 4 / min for 2-oxoglutarate, and a Km of139.7μmol /L and a kcat of 53. 4/ min for arginine. Compared to the extensively studied EFE from Pseudomonassyringae(PsEFE), NpEFE showed less substrate inhibition and al-most two-fold higher activity than PsEFE at high substrate concentrations. Therefore, NpEFE would be more potential in future ethylene industrial bioproduction.

Key words: ethylene forming enzyme, ethylene, substrate inhibition, 2-oxoglutarate dependent protein