This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Reprints and Permissions Copyright Information Books from ASM Press MicrobeWorld Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Barkay, T. Articles by Turner, R. R. Search for Related Content PubMed PubMed Citation Articles by Barkay, T. Articles by Turner, R. R. Agricola Articles by Barkay, T. Articles by Turner, R. R.

 Previous Article  |  Next Article 

Appl. Environ. Microbiol., Nov 1997, 4267-4271, Vol 63, No. 11
Copyright © 1997, American Society for Microbiology

Effects of dissolved organic carbon and salinity on bioavailability of mercury

T Barkay, M Gillman and RR Turner
Gulf Ecology Division, National Health and Environmental Effects Laboratory, U.S. Environmental Protection Agency, Gulf Breeze, Florida 32561, USA. tbarkay@post.tau.ac.il

Hypotheses that dissolved organic carbon (DOC) and electrochemical charge affect the rate of methylmercury [CH3Hg(I)] synthesis by modulating the availability of ionic mercury [Hg(II)] to bacteria were tested by using a mer-lux bioindicator (O. Selifonova, R. Burlage, and T. Barkay, Appl. Environ. Microbiol. 59:3083-3090, 1993). A decline in Hg(II)-dependent light production was observed in the presence of increasing concentrations of DOC, and this decline was more pronounced at pH 7 than at pH 5, suggesting that DOC is a factor controlling the bioavailability of Hg(II). A thermodynamic model (MINTEQA2) was used to select assay conditions that clearly distinguished among various Hg(II) species. By using this approach, it was shown that negatively charged forms of mercuric chloride (HgCl3-/HgCl(4)2-) induced less light production than the electrochemically neutral form (HgCl2), and no difference was observed between the two neutral forms, HgCl2 and Hg(OH)2. These results suggest that the negative charge of Hg(II) species reduces their availability to bacteria and may be one reason why accumulation of CH3Hg(I) is more often reported to occur in freshwater than in estuarine and marine biota.

This article has been cited by other articles:

• Golding, G. R., Sparling, R., Kelly, C. A. (2008). Effect of pH on Intracellular Accumulation of Trace Concentrations of Hg(II) in Escherichia coli under Anaerobic Conditions, as Measured Using a mer-lux Bioreporter. Appl. Environ. Microbiol. 74: 667-675 [Abstract] [Full Text]  
• Poulain, A. J., Ni Chadhain, S. M., Ariya, P. A., Amyot, M., Garcia, E., Campbell, P. G. C., Zylstra, G. J., Barkay, T. (2007). Potential for Mercury Reduction by Microbes in the High Arctic. Appl. Environ. Microbiol. 73: 2230-2238 [Abstract] [Full Text]  
• Siciliano, S. D., Sangster, A., Daughney, C. J., Loseto, L., Germida, J. J., Rencz, A. N., O'Driscoll, N. J., Lean, D. R. S. (2003). Are Methylmercury Concentrations in the Wetlands of Kejimkujik National Park, Nova Scotia, Canada, Dependent on Geology?. J. Environ. Qual. 32: 2085-2094 [Abstract] [Full Text]  
• Ekstrom, E. B., Morel, F. M. M., Benoit, J. M. (2003). Mercury Methylation Independent of the Acetyl-Coenzyme A Pathway in Sulfate-Reducing Bacteria. Appl. Environ. Microbiol. 69: 5414-5422 [Abstract] [Full Text]  
• Jay, J. A., Murray, K. J., Gilmour, C. C., Mason, R. P., Morel, F. M. M., Roberts, A. L., Hemond, H. F. (2002). Mercury Methylation by Desulfovibrio desulfuricans ND132 in the Presence of Polysulfides. Appl. Environ. Microbiol. 68: 5741-5745 [Abstract] [Full Text]  
• Bonzongo, J. C., Bonzongo, J. C., Lyons, W. B., Hines, M. E., Warwick, J. J., Faganeli, J., Horvat, M., Lechler, P. J., Miller, J. R. (2002). Mercury in surface waters of three mine-dominated river systems: Idrija River, Slovenia; Carson River, Nevada; and Madeira River, Brazilian Amazon. Geochem. 2: 111-119 [Abstract] [Full Text]  
• King, J. K., Kostka, J. E., Frischer, M. E., Saunders, F. M. (2000). Sulfate-Reducing Bacteria Methylate Mercury at Variable Rates in Pure Culture and in Marine Sediments. Appl. Environ. Microbiol. 66: 2430-2437 [Abstract] [Full Text]  
• von Canstein, H., Li, Y., Timmis, K. N., Deckwer, W.-D., Wagner-Döbler, I. (1999). Removal of Mercury from Chloralkali Electrolysis Wastewater by a Mercury-Resistant Pseudomonas putida Strain. Appl. Environ. Microbiol. 65: 5279-5284 [Abstract] [Full Text]  
• Gupta, A., Maynes, M., Silver, S. (1998). Effects of Halides on Plasmid-Mediated Silver Resistance in Escherichia coli. Appl. Environ. Microbiol. 64: 5042-5045 [Abstract] [Full Text]