Expression of Active Subunit of Nitrogenase via Integration into Plant Organelle Genome

Nitrogen availability is crucial for crop yield with nitrogen fertilizer accounting for a large percentage of farmers' expenses. However, an untimely or excessive application of fertilizer can increase risks of negative environmental effects. These factors, along with the environmental and energy costs of synthesizing nitrogen fertilizer, led us to seek out novel biotechnology-driven approaches to supply nitrogen to plants. The strategy we focused on involves transgenic expression of nitrogenase, a bacterial multi-subunit enzyme that can capture atmospheric nitrogen. Here we report expression of the active Fe subunit of nitrogenase via integration into the tobacco plastid genome of bacterial gene sequences modified for expression in plastid. Our study suggests that it will be possible to engineer plants that are able to produce their own nitrogen fertilizer by expressing nitrogenase genes in plant plastids.