In the August 2011 issue of the Journal of Bacteriology, a team of researchers led by DOE JGI’s Patrick Chain at Los Alamos National Laboratory focused on a microbe that can help or harm as the case may be.
Rhizosphere, magnified 10,000X (Image by Sandra Silvers, USDA-ARS)
Ochrobactrum anthropi thrives in a variety of habitats including polluted soil, plants and even higher mammals. One strain of O. anthropi can degrade the compounds used as slow-release nitrogen fertilizer, while another strain can enhance tea plant growth and decrease the incidence of brown root rot in the same plant. Still another strain is an opportunistic pathogen in hospitalized patients.
The 4.8- million base pair genome of O.anthropi was selected for sequencing by the DOE JGI in part, wrote Chain and his colleagues, because of “its phylogenetic proximity to the highly pathogenic brucellae,” microbes considered by the US. Department of Agriculture to be a “severe threat to public, animal or plant health.”
Understanding the interactions between soil microbes and plants is one of the reasons the DOE JGI selected this topic area as of its Grand Challenge projects focusing on the rhizosphere, that underground region where the plant roots, soil microbes and the soil itself interact with one another.
Among the objectives of this Grand Challenge project is understanding how the complex interactions between the various organisms in this region contribute to the rhizosphere’s role in terrestrial carbon sequestration, and how genomics can enhance such beneficial relationships between plants and microbes.