Role of the nifM in maturation of the Fe-protein of nitrogenase

摘要

Nitrogenase is composed of two separate proteins designated the Fe-protein and the MoFe-protein. The Fe-protein of nitrogenase has been reported to have four distinct functions. In order for N_2 reduction to occur, the Fe-protein must transfer electrons to the MoFe-protein (Howard, Rees 2000; Burgess, Lowe 1996). The Fe-protein is a dimer that couples the hydrolysis of two MgATPs to the transfer of a single electron; and in addition, it is also associated with the precursor of the MoFe-protein, apodinitrogenase, to facilitate its activation with the FeMo-cofactor. Our comparison of the polypeptide sequences of different Fe-proteins has revealed the existence of a remarkable degree of conservation of the amino acid sequence. A consensus sequence forthe Fe-protein derived from this analysis is shown in Figure 1.