The goals of this project are to understand how certain types of bacteria are capable of supplying themselves with nitrogen fertilizer, which is required for the growth of all organisms. The project will determine at the cellular and molecular level, how these bacteria, called cyanobacteria, produce the cells and enzymes that "fix" nitrogen from the air to produce compounds that can enter cell metabolism. Cyanobacteria are green in color and obtain energy from sunlight with photosynthesis similarly to plants. Like algae, cyanobacteria are important primary producers, which are food for other organisms, in many environments, especially the oceans, and they remove carbon dioxide from the atmosphere, which reduces effects of global warming. Nitrogen-fixing cyanobacteria provide biologically available nitrogen in natural environments and are used as nitrogen fertilizer for rice cultivation in some parts of the world. Recently, there has been enormous interest in using cyanobacteria and algae to capture energy from sunlight to produce biomass, biofuels such as biodiesel and ethanol, and hydrogen gas. This project will use the well-established model organism Anabaena to determine how specialized cells called heterocysts produce the enzymes required for nitrogen fixation. The project will use methods of genetics, molecular biology, and biochemistry to study these processes. This project is expected to reveal new mechanisms of genetic regulation and gene expression in this large and important group of microorganisms. Understanding the mechanisms that control nitrogen-fixation genes will enhance our knowledge of basic microbial biology, genetics, and metabolism, and will provide knowledge that can be applied to industrial carbon capture and biofuel production. During the course of this project, undergraduate, graduate, and postdoctoral students will receive training in state-of-the-art research methods. The research will also produce materials and methods that will be useful to other researchers in both academia and industry, and the long-term goals of this project will benefit society by providing basic knowledge related to natural ecosystems, agriculture, global warming, and biofuels.
