Mercury methylation by dissimilatory iron-reducing bacteria.

Title of Document : MERCURY METHYLATION IN DISSIMILATORY IRON - REDUCING BACTERIA

Title of Document: MERCURY METHYLATION IN DISSIMILATORY IRON-REDUCING BACTERIA 22BElizabeth Johanna Kerin, Master of Science, 2007 Directed By: Dr. Marcelino Suzuki, Marine, Estuarine and Environmental Sciences Microbial mercury methylation is an integral factor controlling methylmercury concentrations within aquatic ecosystems. This thesis explores the phylogenetic distribution and biochemistr...

Mercury methylation from unexpected sources: molybdate-inhibited freshwater sediments and an iron-reducing bacterium.

Methylmercury has been thought to be produced predominantly by sulfate-reducing bacteria in anoxic sediments. Here we show that in circumneutral pH sediments (Clear Lake, CA) application of a specific inhibitor of sulfate-reducing bacteria at appropriate concentrations typically inhibited less than one-half of all anaerobic methylation of added divalent mercury. This suggests that one or more a...

279. Dissimilatory Fe(III)- and Mn(IV)-Reducing Prokaryotes

Dissimilatory Fe(III) reduction is the process in which microorganisms transfer electrons to external ferric iron [Fe(III)], reducing it to ferrous iron [Fe(II)] without assimilating the iron. A wide phylogenetic diversity of microorganisms, including archaea as well as bacteria, are capable of dissimilatory Fe(III) reduction. Most microorganisms that reduce Fe(III) also can transfer electrons ...

Microbial mercury transformation in anoxic freshwater sediments under iron-reducing and other electron-accepting conditions.

Potential rates of microbial methylation of inorganic mercury (added as HgCl2) and degradation of methyl mercury (MeHg) (added as CH3HgCl) were investigated in anoxic sediments from the Mobile Alabama River Basin (MARB) dominated by different terminal electron-accepting processes (TEAPs). Potential rates of methylation were comparable under methanogenic and sulfate-reducing conditions but suppr...

Assessing Mutualism Between Dissimilatory Ferric Iron- and Sulfate-Reducing Bacteria