BER launches Environmental System Science Program. Visit our new website under construction!

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

BER Research Highlights


How Sulfur Affects Chemistry of Iron in the Environment
Published: May 30, 2014
Posted: January 06, 2017

Substantial amounts of iron are present in many subsurface environments. This element has a significant effect on both the biogeochemical cycling of carbon and the fate and transport of trace environmental contaminants, because it is readily transformed among several reactive species. The interactions of subsurface iron with various naturally occurring bacteria have a major influence on its environmental impacts, but these interactions are not well understood. Scientists at Argonne National Laboratory and three partner universities have identified a key role for sulfur in how bacteria affect the speciation of subsurface iron. They determined that bacteria unable to reduce ferric iron directly under alkaline conditions can do so indirectly. The bacteria do this by reducing elemental sulfur to sulfide ion, which then reduces the ferric iron in the goethite to ferrous iron. In addition, this ferrous iron can reduce other metal species such as uranyl ion, thus affecting their solubility. The researchers determined that this process is common in alkaline environments such aquifers, especially those in arid regions. This new understanding of this environmental role of iron will enable progress in a wide range of areas, from modeling of potential carbon capture systems to understanding speciation of contaminants such as uranium and arsenic.

References: Flynn, T. M., E. J. O’Loughlin, B. Mishra, T. J. DiChristina, and K. M. Kemner. 2014. “Sulfur-Mediated Electron Shuttling During Bacterial Iron Reduction,”, Science 344, 1039-42. DOI: 10.1126/science.1252066. (Reference link)

Friedrich, M. W., and K. W. Finster. 2014. “How Sulfur Beats Iron,” Science 344, 974-75. DOI: 10.1126/science.1255442. (Reference link)

Contact: Roland F. Hirsch, SC-23.2, roland.hirsch@science.doe.gov, 301-903-9009.

Topic Areas:

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

Division: SC-33.1 Earth 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

Jan 11, 2022
No Honor Among Copper Thieves
Findings provide a novel means to manipulate methanotrophs for a variety of environmental and in [more...]

Dec 06, 2021
New Genome Editing Tools Can Edit Within Microbial Communities
Two new technologies allow scientists to edit specific species and genes within complex laborato [more...]

Oct 27, 2021
Fungal Recyclers: Fungi Reuse Fire-Altered Organic Matter
Degrading pyrogenic (fire-affected) organic matter is an important ecosystem function of fungi i [more...]

Oct 19, 2021
Microbes Offer a Glimpse into the Future of Climate Change
Scientists identify key features in microbes that predict how warming affects carbon dioxide emi [more...]

Aug 25, 2021
Assessing the Production Cost and Carbon Footprint of a Promising Aviation Biofuel
Biomass-derived DMCO has the potential to serve as a low-carbon, high-performance jet fuel blend [more...]

List all highlights (possible long download time)