Biosynthesis of nitrogenase FeMoco

Biosynthesis of nitrogenase FeMoco is a highly complex process that requires, minimally, the participation of nifS, nifU, nifB, nifE, nifN, nifV, nifH, nifD and nifK gene products. Previous genetic analyses have identified the essential factors for the assembly of FeMoco; however, the exact functions of these factors and the precise sequence of events during the assembly process had remained unclear until recently, when a number of the biosynthetic intermediates of FeMoco were identified and characterized by combined biochemical, spectroscopic and structural analyses. This review gives a brief account of the recent progress toward understanding the assembly process of FeMoco, which has identified some important missing pieces of this biosynthetic puzzle.

Graphical abstractFigure optionsDownload full-size imageDownload high-quality image (159 K)Download as PowerPoint slideResearch highlights▶ NifEN accumulates an all-Fe precursor closely resembling the Fe–S core of FeMoco. ▶ NifEN provides a scaffold for the maturation of the all-Fe precursor. ▶ Fe protein inserts Mo and homocitrate in the precursor on NifEN upon ATP hydrolysis. ▶ FeMoco is transferred from NifEN to MoFe protein upon protein–protein interactions. ▶ FeMoco is inserted into MoFe protein via a positively charged insertion funnel.