Reaction: 8 reduced ferredoxin + 8 H+ + N2 + 16 ATP + 16 H2O = 8 oxidized ferredoxin + H2 + 2 NH3 + 16 ADP + 16 phosphate
For diagram of reaction click here.
Other name(s): reduced ferredoxin:dinitrogen oxidoreductase (ATP-hydrolysing)
Systematic name: ferredoxin:dinitrogen oxidoreductase (ATP-hydrolysing, molybdenum-dependent)
Comments: Requires Mg2+. The enzyme is a complex of two components (namely dinitrogen reductase and dinitrogenase). Dinitrogen reductase is a [4Fe-4S] protein, which, in the presence of two molecules of ATP, transfers an electron from ferredoxin to the dinitrogenase component. Dinitrogenase is a molybdenum-iron protein that reduces dinitrogen to two molecules of ammonia in three successive two-electron reductions via diazene and hydrazine. The reduction is initiated by formation of hydrogen in stoichiometric amounts . Acetylene is reduced to ethylene (but only very slowly to ethane), azide to nitrogen and ammonia, and cyanide to methane and ammonia. In the absence of a suitable substrate, hydrogen is slowly formed. Ferredoxin may be replaced by flavodoxin [see EC 220.127.116.11 nitrogenase (flavodoxin)]. The enzyme does not reduce CO (cf. EC 18.104.22.168, vanadium-dependent nitrogenase).
Links to other databases: BRENDA, EXPASY, KEGG, MetaCyc, PDB, UM-BBD, CAS registry number: 9013-04-1
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