U.S. Department of Energy Office of Biological and Environmental Research

BER Research Highlights

How Phosphate Ion Influences Cycling of Carbon and Iron in the Environment
Published: August 02, 2013
Posted: September 12, 2013

Subsurface microbes convert iron among several chemical species. These forms of iron can influence the immobilization and release of contaminant metals such as uranium as well as sequestration of carbon. Predictive understanding of the processes involved in these transformations is limited by a lack of knowledge of the impact of many other chemical species commonly found with iron in the subsurface. New research by scientists at Argonne National Laboratory and collaborating universities has provided knowledge of how phosphate ion incorporated in iron-containing minerals affects the speciation of iron and cycling of carbonate ion (a common form of carbon in the subsurface). These scientists determined that the phosphate bound or occluded within the Fe(III)-containing particles has a significant impact on the minerals produced by the iron-reducing bacterium Shewanella putrefaciens . In the absence of phosphate, the Fe(III) is largely converted to magnetite, but when phosphate is present within the Fe(III) particles, a significant amount of a reactive iron-containing species known as green rust is produced. Green rust is highly effective in reducing and immobilizing contaminants such as radionuclides and toxic metals. This study therefore provides key information for understanding how to efficiently use Shewanella to treat contaminated environments.

Reference: O'Loughlin, E. J., M. I. Boyanov, T. M. Flynn, C. Gorski, S. M. Hofmann, M. L. McCormick, M. M. Scherer, and K. M. Kemner. 2013. “Effects of Bound Phosphate on the Bioreduction of Lepidocrocite (γ-FeOOH) and Maghemite (γ-Fe2O3) and Formation of Secondary Minerals,” Environmental Science and Technology 47 , 9157–66. DOI: 10.1021/es400627j. (Reference link)

Contact: Roland F. Hirsch, SC-23.2, (301) 903-9009
Topic Areas:

  • Research Area: Subsurface Biogeochemical Research
  • Research Area: Carbon Cycle, Nutrient Cycling
  • Research Area: Microbes and Communities

Division: SC-23.1 Climate and Environmental Sciences Division, BER


BER supports basic research and scientific user facilities to advance DOE missions in energy and environment. More about BER

Recent Highlights

Aug 24, 2019
New Approach for Studying How Microbes Influence Their Environment
A diverse group of scientists suggests a common framework and targeting of known microbial processes [more...]

Aug 08, 2019
Nutrient-Hungry Peatland Microbes Reduce Carbon Loss Under Warmer Conditions
Enzyme production in peatlands reduces carbon lost to respiration under future high temperatures. [more...]

Aug 05, 2019
Amazon Forest Response to CO2 Fertilization Dependent on Plant Phosphorus Acquisition
AmazonFACE Model Intercomparison. The Science Plant growth is dependent on the availabi [more...]

Jul 29, 2019
A Slippery Slope: Soil Carbon Destabilization
Carbon gain or loss depends on the balance between competing biological, chemical, and physical reac [more...]

Jul 15, 2019
Field Evaluation of Gas Analyzers for Measuring Ecosystem Fluxes
How gas analyzer type and correction method impact measured fluxes. The Science A side- [more...]

List all highlights (possible long download time)