title: Mercury methylation by Desulfovibrio desulfuricans ND132 in the presence of polysulfides.
abstract: The extracellular speciation of mercury may control bacterial uptake and methylation. Mercury-polysulfide complexes have recently been shown to be prevalent in sulfidic waters containing zero-valent sulfur. Despite substantial increases in total dissolved mercury concentration, methylation rates in cultures of Desulfovibrio desulfuricans ND132 equilibrated with cinnabar did not increase in the presence of polysulfides, as expected due to the large size and charged nature of most of the complexes. In natural waters not at saturation with cinnabar, mercury-polysulfide complexes would be expected to shift the speciation of mercury from HgS(0)((aq)) toward charged complexes, thereby decreasing methylation rates.
authors.affiliation: The Ralph M. Parsons Laboratory, Department of Civil and Environmental Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA. jennyayla@alum.mit.edu
authors.forename: Jenny Ayla
authors.initials: JA
authors.lastname: Jay
authors.forename: Karen J
authors.initials: KJ
authors.lastname: Murray
authors.forename: Cynthia C
authors.initials: CC
authors.lastname: Gilmour
authors.forename: Robert P
authors.initials: RP
authors.lastname: Mason
authors.forename: François M M
authors.initials: FM
authors.lastname: Morel
authors.forename: A Lynn
authors.initials: AL
authors.lastname: Roberts
authors.forename: Harold F
authors.initials: HF
authors.lastname: Hemond
mesh_terms: D002452:Cell Count; D003470:Culture Media; D003901:Desulfovibrio / Q000187:drug effects / Q000254:growth & development / Q000378:metabolism*; D004347:Drug Interactions; D008628:Mercury / Q000378:metabolism*; D008745:Methylation; D012995:Solubility; D013440:Sulfides / Q000378:metabolism / Q000494:pharmacology*
chemical_list: D003470:Culture Media; D013440:Sulfides; C032915:polysulfide; D008628:Mercury