ID 1.18.6.2 DE vanadium-dependent nitrogenase. CA N2 + 12 reduced [2Fe-2S]-[ferredoxin] + 40 ATP + 40 H2O = 3 H2 + CA 12 oxidized [2Fe-2S]-[ferredoxin] + 2 NH4(+) + 40 ADP + 40 phosphate + CA 26 H(+). CC -!- This enzyme, originally isolated from the bacterium Azotobacter CC vinelandii, is a complex of two components (namely dinitrogen CC reductase and dinitrogenase). CC -!- Dinitrogen reductase is a [4Fe-4S] protein, which, in the presence of CC ATP, transfers an electron from ferredoxin to the dinitrogenase CC component. CC -!- Dinitrogenase is a vanadium-iron protein that reduces dinitrogen to CC two molecules of ammonia in three successive two-electron reductions CC via diazine and hydrazine. CC -!- Compared with EC 1.18.6.1, this enzyme produces more dihydrogen and CC consumes more ATP per dinitrogen molecule being reduced. CC -!- Unlike EC 1.18.6.1, this enzyme can also use CO as substrate, CC producing ethylene, ethane and propane. //