Office of Science

Biogeochemistry Grand Challenge

Shewanella oneidensis MR-1 growing on a hematite surface
Shewanella oneidensis MR-1 growing on a hematite surface.

A Grand Challenge in biogeochemistry, led by PNNL scientists Dr. John Zachara and Dr. Jim Fredrickson is studying how organisms exchange energy and electron flux with mineral matter in soils, sediments, and subsurface materials. This exchange occurs across a mineral-microbe interface that is a minute, but chemically active domain whose molecular workings have perplexed scientists for decades. The biogeochemistry Grand Challenge will use advanced instrumental capabilities and the high performance computing capabilities of EMSL to understand the biologic and physical architecture of this remarkably complex domain and the microbe-mediated chemical reactions that occur within it. The research will allow scientists to understand this most basic earth-life interaction that is fundamental to the migration of environmental contaminants, to water quality, and to soil fertility and trace metal availability.

  1. Bioreduction of hematite nanoparticles by the dissimilatory iron reducing bacterium Shewanella oneidensis MR-1.
  2. Electron donor-dependent radionuclide reduction and nanoparticle formation by Anaeromyxobacter dehalogenans strain 2CP-C.
  3. Interaction between the CBM of Cel9A from Thermobifida fusca and Cellulose Fibers.
  4. Antibody recognition force microscopy shows that outer membrane cytochromes OmcA and MtrC are expressed on the exterior surface of Shewanella oneidensis MR-1.
  5. Electrostatic Cooperativity of Hydroxyl Groups at Metal Oxide Surfaces.

Lead Investigators:
John Zachara, EMSL | | (509) 371-6549

Jim Fredrickson, Pacific Northwest National Laboratory | | (509) 376-7063