HR: 1340h
AN: B13A-1033    [Abstracts]
TI: Visualization of Mercury Methylating Pure-Culture Sulfate-Reducing Biofilms
AU: Lin, C
EM: chuching@ucla.edu
AF: Civil and Environmental Engineering, UCLA, 5731-5732 Boelter Hall, Los Angeles, CA 90095-1593 United States
AU: * Reyes, C
EM: creyes6@gmail.com
AF: Civil and Environmental Engineering, UCLA, 5731-5732 Boelter Hall, Los Angeles, CA 90095-1593 United States
AU: Mendez, C
EM: carol_mendez@hotmail.com
AF: Civil and Environmental Engineering, UCLA, 5731-5732 Boelter Hall, Los Angeles, CA 90095-1593 United States
AU: Jay, J A
EM: jjay@seas.ucla.edu
AF: Civil and Environmental Engineering, UCLA, 5731-5732 Boelter Hall, Los Angeles, CA 90095-1593 United States
AB: Methylmercury is a potent neurotoxin that can accumulate in food chains posing a serious ecological problem in certain aquatic systems. Relatively less toxic inorganic mercury (Hg) is converted to methylmercury (CH3Hg+) by bacteria, and it has been shown that sulfate reducing bacteria (SRB) are the major mediators of this process in many aquatic systems. To date, all laboratory studies on bacterial mercury methylation by SRB have been conducted using planktonic, free floating, bacterial cultures, yet bacteria exist mostly as attached communities or biofilms in the environment. We hypothesized that biofilms composed of different SRB would differ in their ability to bind and methylate mercury compared to planktonic cultures. To test our hypothesis ten SRB isolates capable of producing biofilms in the laboratory were enriched from a marine sediment. We identified the isolates by 16S rDNA sequence analysis, compared pure-culture biofilm structure using fluorescent in situ hybridization (FISH) and confocal microscopy, and measured mercury methylation in biofilms of these SRB.
UR: http://www.cee.ucla.edu/faculty/jayR.htm
DE: 0414 Biogeochemical cycles, processes, and modeling (0412, 0793, 1615, 4805, 4912)
DE: 0432 Contaminant and organic biogeochemistry (0792)
DE: 0461 Metals
DE: 0478 Pollution: urban, regional and global (0345, 4251)
DE: 0497 Wetlands (1890)
SC: Biogeosciences [B]
MN: Fall Meeting 2005