Engineering nitrogenase for plants and fungi – What is achieved and what remains?

In this review we discuss strategies to engineer plants to fix N2, with a special focus on recent advances in biochemistry, synthetic biology and plant biotechnology.


Today, over 80% of the nitrogen in the average human body originates from industrial synthetic fertilizers used in agriculture. These are mainly produced by the Haber-Bosch process, in which H2 and N2 react over a catalyst at high temperature and pressure to generate ammonia (NH3), a biologically active N species. Biological conversion of N2 into NH3, called nitrogen fixation, also exists in a group of bacteria, sometimes in association with plants of the legume family. In contrast, no plant, fungi or animal can fix nitrogen by itself. To reduce costs and negative effects on nature from large use of fertilizers, improving the ability of plants and plant-associated microorganisms to fix nitrogen has inspired plant biotechnologists for decades. Although considered an almost impossible task, recent advances in synthetic biology and genetics of nitrogen fixation has made this vision more realistic. In this review, we discuss strategies and advances towards engineering plants to express its own nitrogenase.

Plant nitrogen fixation: By transferring bacterial nitrogen fixation genetic machinery into plants, these should be able to fix nitrogen on their own, reducing the need for industrial nitrogen fertilizers.

Original Paper:

Burén, S; Rubio, LM. 2017. "State of the art in eukaryotic nitrogenase engineering". FEMS Microbiology Letters. DOI: 10.1093/femsle/fnx274".