DIMCO_N is the N-terminal domain of the gamma (Y) subunit of nitrogenase. An alternative name is NafY_N, for nitrogenase accessory factor Y N-terminal. This region is negatively charged and appears to be necessary for recognising and interacting with the apo state of dinitrogenase. The full-length NafY protein facilitates the transfer of iron-molybdenum cofactor, or FeMo-co, into apodinitrogenase by binding to both. The C-terminal region, family Nitro_FeMo-Co, Pfam:PF02579, is the part that binds to the cofactor, and the N-terminus binds to apodinitrogenase. Nitrogenase is the bacterial enzyme responsible for nitrogen fixation by catalysing the reduction of nitrogen gas (N2) to ammonium in an ATP-dependent manner. It has two components, dinitrogenase and dinitrogenase reductase [1].

1: The three-dimensional structure of the core domain of Naf Y from Azotobacter vinelandii determined at 1.8-A resolution. Dyer DH, Rubio LM, Thoden JB, Holden HM, Ludden PW, Rayment I; J Biol Chem. 2003;278:32150-32156. PMID:12754195