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CATH Superfamily 3.40.50.1980

Nitrogenase molybdenum iron protein domain

The name of this superfamily has been modified since the most recent official CATH+ release (v4_3_0). At the point of the last release, this superfamily was named:

"
Nitrogenase molybdenum iron protein domain
".

Functional Families

Overview of the Structural Clusters (SC) and Functional Families within this CATH Superfamily. Clusters with a representative structure are represented by a filled circle.
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FunFam 46: Nitrogenase molybdenum-iron protein beta chain

There are 1 EC terms in this cluster

Please note: EC annotations are assigned to the full protein sequence rather than individual protein domains. Since a given protein can contain multiple domains, it is possible that some of the annotations below come from additional domains that occur in the same protein, but have been classified elsewhere in CATH.

Note: The search results have been sorted with the annotations that are found most frequently at the top of the list. The results can be filtered by typing text into the search box at the top of the table.

EC Term Annotations Evidence
Nitrogenase. [EC: 1.18.6.1]
8 reduced ferredoxin + 8 H(+) + N(2) + 16 ATP + 16 H(2)O = 8 oxidized ferredoxin + H(2) + 2 NH(3) + 16 ADP + 16 phosphate.
  • The enzyme is a complex of two components (namely dinitrogen reducatse 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 1.19.6.1).
  • The enzyme does not reduce CO (cf. EC 1.18.6.2).
  • Formerly EC 1.18.2.1.
 9 C1DGZ8 C1DGZ8 C1DGZ8 M9YGZ5 M9YGZ5 M9YGZ5 P07329 P07329 P07329