Environmental significance of the potential for mer(Tn21)-mediated reduction of Hg2+ to Hg0 in natural waters

Journal Article · Mon May 01 04:00:00 EDT 1989 · Applied and Environmental Microbiology; (USA)

OSTI ID:5608223

Barkay, T; Liebert, C; Gillman, M ^[1]

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1. Environmental Protection Agency, Gulf Breeze, FL (USA)

The role of mer(Tn21) in the adaptation of aquatic microbial communities to Hg2+ was investigated. Elemental mercury was the sole product of Hg2+ volatilization by freshwater and saline water microbial communities. Bacterial activity was responsible for biotransformation because most microeucaryotes did not survive the exposure conditions, and removal of larger microbes (greater than 1 micromole) from adapted communities did not significantly (P greater than 0.01) reduce Hg2+ volatilization rates. DNA sequences homologous to mer(Tn21) were found in 50% of Hg2+-resistant bacterial strains representing two freshwater communities, but in only 12% of strains representing two saline communities (the difference was highly significant; P less than 0.001). Thus, mer(Tn21) played a significant role in Hg2+ resistance among strains isolated from fresh waters, in which microbial activity had a limited role in Hg2+ volatilization. In saline water environments in which microbially mediated volatilization was the major mechanism of Hg2+ loss, other bacterial genes coded for this biotransformation.

• OSTI ID: 5608223
• Journal Information: Applied and Environmental Microbiology; (USA), Journal Name: Applied and Environmental Microbiology; (USA) Vol. 55:5; ISSN AEMID; ISSN 0099-2240
• Country of Publication: United States
• Language: English

Related Subjects

520200* -- Environment
Aquatic-- Chemicals Monitoring & Transport-- (-1989)
54 ENVIRONMENTAL SCIENCES
560300 -- Chemicals Metabolism & Toxicology
63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTANT EFFECTS ON LIVING ORGS. AND BIOL. MAT.
ANIMALS
BACTERIA
BIODEGRADATION
BIOLOGICAL ADAPTATION
CHEMICAL REACTIONS
DECOMPOSITION
DNA
ELEMENTS
FRESH WATER
GENES
HYDROGEN COMPOUNDS
INVERTEBRATES
MASTIGOPHORA
MERCURY
METALS
MICROORGANISMS
NUCLEIC ACIDS
ORGANIC COMPOUNDS
OXYGEN COMPOUNDS
PROTOZOA
SEAWATER
SENSITIVITY
VOLATILITY
WATER