Evaluation of mercury methylation/demethylation by the microbial community of Tagus estuary using stable Hg isotopes

ABSTRACT Spatial and temporal variations in sediment microbial community structure in a eutrophic lake polluted with inorganic mercury were identified using polar lipid fatty acid (PLFA) analysis. Microbial community structure was strongly related to mercury methylation potential, sediment organic carbon content, and lake location. Pore water sulfate, total mercury concentrations, and organic matter C/N ratios showed no relationships with microbial community structure. Seasonal changes and changes potentially attributable to temperature regulation of bacterial membranes were detectable but were less important influences on sediment PLFA composition than were differences due to lake sampling location. Analysis of biomarker PLFAs characteristic of Desulfobacter andDesulfovibrio groups of sulfate-reducing bacteria suggests that Desulfobacter-like organisms are important mercury methylators in the sediments, especially in the Lower Arm of Clear Lake.

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A method for measuring the response of sediment microbial communities to environmental perturbations

Canadian Journal of Microbiology ◽

10.1139/m84-224 ◽

1984 ◽

Vol 30 (11) ◽

pp. 1408-1414 ◽

Cited By ~ 24

Author(s):

Akira Furutani ◽

John W. M. Rudd ◽

C. A. Kelly

Keyword(s):

Organic Matter ◽

Microbial Community ◽

Microbial Communities ◽

Nitrate Reduction ◽

Microbial Processes ◽

Mercury Methylation ◽

Community Activity ◽

Environmental Perturbations ◽

Comprehensive Information

A method has been developed for studying direct and indirect responses of microbial processes in lake sediments to environmental perturbations. Responses of the entire microbial community as well as specific members of the community were studied using in vitro sediment systems for periods of weeks or months under control and experimentally perturbed conditions. Effects of perturbations at the community level were determined by comparing rates of organic matter decomposition (CO2 + CH4 production) in the control and test (acidified) systems. At the same time and under the same conditions, rates of specific processes such as mercury methylation and sulfate and nitrate reduction were assayed to see if these processes responded in the same manner as did the activity of the entire community. Acidification (lowering from pH 6.3 to 4.2) did not affect either community activity or nitrate reduction. However, decreases were observed in sulfate reduction and mercury methylation which were independent of community activity, suggesting that acidification may affect these two specific processes directly. Use of this method provides comprehensive information about the interaction of sediment microbial processes as they respond to environmental perturbations.

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Evidence of Mercury Methylation and Demethylation by the Estuarine Microbial Communities Obtained in Stable Hg Isotope Studies

International Journal of Environmental Research and Public Health ◽

10.3390/ijerph15102141 ◽

2018 ◽

Vol 15 (10) ◽

pp. 2141 ◽

Cited By ~ 4

Author(s):

Neusa Figueiredo ◽

Maria Serralheiro ◽

João Canário ◽

Aida Duarte ◽

Holger Hintelmann ◽

...

Keyword(s):

Microbial Communities ◽

Critical Factor ◽

High Rate ◽

Mercury Removal ◽

Tagus Estuary ◽

Simultaneous Occurrence ◽

Mercury Methylation ◽

Aquatic Environments ◽

Isotope Studies ◽

Microbial Methylation

Microbial activity is a critical factor controlling methylmercury formation in aquatic environments. Microbial communities were isolated from sediments of two highly mercury-polluted areas of the Tagus Estuary (Barreiro and Cala do Norte) and differentiated according to their dependence on oxygen into three groups: aerobic, anaerobic, and sulphate-reducing microbial communities. Their potential to methylate mercury and demethylate methylmercury was evaluated through incubation with isotope-enriched Hg species (199HgCl and CH3201HgCl). The results showed that the isolated microbial communities are actively involved in methylation and demethylation processes. The production of CH3199Hg was positively correlated with sulphate-reducing microbial communities, methylating up to 0.07% of the added 199Hg within 48 h of incubation. A high rate of CH3201Hg degradation was observed and >20% of CH3201Hg was transformed. Mercury removal of inorganic forms was also observed. The results prove the simultaneous occurrence of microbial methylation and demethylation processes and indicate that microorganisms are mainly responsible for methylmercury formation and accumulation in the polluted Tagus Estuary.

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Mercury methylation by a microbial community from sediments of the Adour Estuary (Bay of Biscay, France)

Environmental Pollution ◽

10.1016/j.envpol.2008.05.007 ◽

2008 ◽

Vol 156 (3) ◽

pp. 951-958 ◽

Cited By ~ 41

Author(s):

R. Duran ◽

M. Ranchou-Peyruse ◽

V. Menuet ◽

M. Monperrus ◽

G. Bareille ◽

...

Keyword(s):

Microbial Community ◽

Mercury Methylation ◽

Bay Of Biscay

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Spatial and seasonal variations in mercury methylation and microbial community structure in a historic mercury mining area, Yolo County, California

Chemical Geology ◽

10.1016/j.chemgeo.2009.03.031 ◽

2009 ◽

Vol 267 (1-2) ◽

pp. 85-95 ◽

Cited By ~ 20

Author(s):

JoAnn M. Holloway ◽

Martin B. Goldhaber ◽

Kate M. Scow ◽

Rebecca E. Drenovsky

Keyword(s):

Community Structure ◽

Microbial Community ◽

Microbial Community Structure ◽

Seasonal Variations ◽

Mining Area ◽

Mercury Methylation ◽

Yolo County ◽

Mercury Mining

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A peek in the micro-sized world: a review of design principles, engineering tools, and applications of engineered microbial community

Biochemical Society Transactions ◽

10.1042/bst20190172 ◽

2020 ◽

Vol 48 (2) ◽

pp. 399-409

Author(s):

Baizhen Gao ◽

Rushant Sabnis ◽

Tommaso Costantini ◽

Robert Jinkerson ◽

Qing Sun

Keyword(s):

Microbial Community ◽

Microbial Communities ◽

Environmental Remediation ◽

Real Life ◽

Design Principles ◽

Microbial Interactions ◽

Potential Applications ◽

New Gene ◽

Global Biogeochemical Cycles ◽

Synthetic Microbial Communities

Microbial communities drive diverse processes that impact nearly everything on this planet, from global biogeochemical cycles to human health. Harnessing the power of these microorganisms could provide solutions to many of the challenges that face society. However, naturally occurring microbial communities are not optimized for anthropogenic use. An emerging area of research is focusing on engineering synthetic microbial communities to carry out predefined functions. Microbial community engineers are applying design principles like top-down and bottom-up approaches to create synthetic microbial communities having a myriad of real-life applications in health care, disease prevention, and environmental remediation. Multiple genetic engineering tools and delivery approaches can be used to ‘knock-in' new gene functions into microbial communities. A systematic study of the microbial interactions, community assembling principles, and engineering tools are necessary for us to understand the microbial community and to better utilize them. Continued analysis and effort are required to further the current and potential applications of synthetic microbial communities.

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