Skip to main content
U.S. flag

An official website of the United States government

The effect of natural organic matter on mercury methylation by Desulfobulbus propionicus 1pr3

December 1, 2015

Methylation of tracer and ambient mercury (200Hg and 202Hg, respectively) equilibrated with four different natural organic matter (NOM) isolates was investigated in vivo using the Hg-methylating sulfate-reducing bacterium Desulfobulbus propionicus 1pr3. Desulfobulbus cultures grown fermentatively with environmentally representative concentrations of dissolved NOM isolates, Hg[II], and HS were assayed for absolute methylmercury (MeHg) concentration and conversion of Hg(II) to MeHg relative to total unfiltered Hg(II). Results showed the 200Hg tracer was methylated more efficiently in the presence of hydrophobic NOM isolates than in the presence of transphilic NOM, or in the absence of NOM. Different NOM isolates were associated with variable methylation efficiencies for either the 202Hg tracer or ambient 200Hg. One hydrophobic NOM, F1 HpoA derived from dissolved organic matter from the Florida Everglades, was equilibrated for different times with Hg tracer, which resulted in different methylation rates. A 5 day equilibration with F1 HpoA resulted in more MeHg production than either the 4 h or 30 day equilibration periods, suggesting a time dependence for NOM-enhanced Hg bioavailability for methylation.

Citation Information

Publication Year 2015
Title The effect of natural organic matter on mercury methylation by Desulfobulbus propionicus 1pr3
DOI 10.3389/fmicb.2015.01389
Authors John W. Moreau, Caitlin M. Gionfriddo, David P. Krabbenhoft, Jacob M. Ogorek, John F. DeWild, George R. Aiken, Eric E. Roden
Publication Type Article
Publication Subtype Journal Article
Series Title Frontiers in Microbiology
Series Number
Index ID 70189516
Record Source USGS Publications Warehouse
USGS Organization Toxic Substances Hydrology Program