Mutagenic and Oncogenic Effects of Chloromethanes, Chloroethanes and Halogenated Analogues of Vinyl Chloride

Infante, Peter F.; Tsongas, Theodora A.

doi:10.1007/978-1-4613-3455-2_23

Cited by 24 publications

(23 citation statements)

References 18 publications

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“…Emission of the compounds into the environment causes contamination of groundwater, soil and sediments. This pollution poses serious health problems because of the toxic and carcinogenic properties of the compounds (Davidson et al, 1982 ;Infante & Tsongas, 1982). Gram-positive and -negative bacteria that degrade chlorinated aliphatic hydrocarbons aerobically have been found by many investigators.…”

Section: Introductionmentioning

confidence: 99%

Janibacter brevis sp. nov., a new trichloroethylene-degrading bacterium isolated from polluted environments.

Imamura¹,

Ikeda²,

Yoshida³

et al. 2000

International Journal of Systematic and Evolutionary Microbiology

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Two strains that were strongly able to degrade trichloroethylene were isolated from contaminated environmental samples. The isolates are non-motile, aerobic, non-spore-forming, Gram-positive coccoid to short rods with cell-wall peptidoglycan containing meso-diaminopimelic acid. The major type of menaquinone is MK-8(H 4 ). The polar lipids were diphosphatidylglycerol, phosphatidylglycerol and phosphatidylinositol. Mycolic acids were absent. The G MC content of the DNA was 72 mol %. Furthermore, comparison of 16S rDNA sequences shows that the isolates clearly belong to the genus Janibacter. The isolates differ from Janibacter limosus at the species level, as shown by the value for DNA-DNA hybridization. It is therefore proposed that the strains be assigned to the genus Janibacter as Janibacter brevis sp. nov.

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Section: Introductionmentioning

confidence: 99%

Janibacter brevis sp. nov., a new trichloroethylene-degrading bacterium isolated from polluted environments.

Imamura¹,

Ikeda²,

Yoshida³

et al. 2000

International Journal of Systematic and Evolutionary Microbiology

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“…TCE), many of which are suspected carcinogens (US EPA, 1981;Imfante & Tsongas, 1982;Westrick et al, 1984;US EPA, 1984). Due to the natural flow of groundwater and dispersive transport processes, aquifer contamination at such sites has usually resulted in large, dilute, migrating plumes that can extend tens of metres in depth (Layton, 1989).…”

Section: Introductionmentioning

confidence: 99%

In situbioremediation of trichloroethylene-contaminated water by a resting-cell methanotrophic microbial filter

Taylor

Hanna

Shah

et al. 1993

Hydrological Sciences Journal

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An in situ microbial filter technology is being tested and developed for remediating migrating subsurface plumes contaminated with low concentrations of trichloroethylene (TCE). The current focus is the establishment of a replenishable bioactive zone (catalytic filter) along expanding plume boundaries by the injection of a representative methanotrophic bacterium, Methylosinus trichosporium OB3b. This microbial filter strategy has been successfully demonstrated using emplaced, attached resting cells (no methane additions) in a 1.1 m flow-through test bed loaded with water-saturated sand. Two separate 24 h pulses of TCE (109 ppb and 85 ppb), one week apart, were pumped through the system at a flow velocity of 15 mm h" 1 ; no TCE ( < 0.5 ppb) was detected on the downstream side of the microbial filter. Subsequent excavation of the wet sand confirmed the existence of a TCE-bioactive zone 21 days after it had been created. An enhanced longevity of the cellular, soluble-form methane monooxygenase produced by this methanotroph is a result of the laboratory bioreactor culturing conditions. Additional experiments with cells in sealed vials and emplaced in the 1.1 m test bed yielded a high resting-cell finite TCE biotransformation capacity of about 0.25 mg per mg of bacteria; this is suitable for a planned sand-filled trench field demonstration at a Lawrence Livermore National Laboratory site.

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“…Although TCE can be reductively dehalogenated under anaerobic conditions, a common end product of this reaction is vinyl chloride, which is more water soluble than TCE and is a known human carcinogen (4,21,48). Removal of TCE from polluted sites or industrial discharge is therefore of great concern.…”

mentioning

confidence: 99%

Cytotoxicity Associated with Trichloroethylene Oxidation in Burkholderia cepacia G4

Yeager¹,

Bottomley

Arp

2001

Appl Environ Microbiol

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The effects of trichloroethylene (TCE) oxidation on toluene 2-monooxygenase activity, general respiratory activity, and cell culturability were examined in the toluene-oxidizing bacterium Burkholderia cepacia G4. Nonspecific damage outpaced inactivation of toluene 2-monooxygenase in B. cepacia G4 cells. Cells that had degraded approximately 0.5 mol of TCE (mg of cells ؊1 ) lost 95% of their acetate-dependent O 2 uptake activity (a measure of general respiratory activity), yet toluene-dependent O 2 uptake activity decreased only 35%. Cell culturability also decreased upon TCE oxidation; however, the extent of loss varied greatly (up to 3 orders of magnitude) with the method of assessment. Addition of catalase or sodium pyruvate to the surfaces of agar plates increased enumeration of TCE-injured cells by as much as 100-fold, indicating that the TCE-injured cells were ultrasensitive to oxidative stress. Cell suspensions that had oxidized TCE recovered the ability to grow in liquid minimal medium containing lactate or phenol, but recovery was delayed substantially when TCE degradation approached 0.5 mol (mg of cells ), up to 90% were Tol ؊ variants, no longer capable of TCE degradation. These results indicate that a toxicity threshold for TCE oxidation exists in B. cepacia G4 and that once a cell suspension has exceeded this toxicity threshold, the likelihood of reestablishing an active, TCE-degrading biomass from the cells will decrease significantly.Trichloroethylene (TCE), a suspected human carcinogen, is one of the most widespread groundwater contaminants. Although TCE can be reductively dehalogenated under anaerobic conditions, a common end product of this reaction is vinyl chloride, which is more water soluble than TCE and is a known human carcinogen (4, 21, 48). Removal of TCE from polluted sites or industrial discharge is therefore of great concern. Although TCE has not been shown to support microbial growth under aerobic conditions, a number of bacteria are capable of degrading this compound via aerobic cometabolism. In each case examined to date, a nonspecific oxygenase catalyzes TCE transformation. Bacterial strains that use oxygenases to grow on methane, butane, propene, ethylene, ammonia, toluene, phenol, isoprene, and dichlorophenoxyacetic acid have been characterized as TCE degraders (3,8,10,11,17,18,39,45,54). Although some of these bacteria exhibit high initial rates of TCE conversion, the process is invariably nonsustainable in the absence of a growth-supporting substrate (2,19,35,49).From the biological standpoint, aerobic cometabolism of TCE by microorganisms is largely dependent on two factors: (i) cellular energy requirements and (ii) the toxicity often associated with TCE oxidation. Energy problems can be overcome by carefully controlling the concentrations of the cometabolite and growth substrate (6, 9) or by selecting or designing microorganisms that are capable of expressing the TCE-degrading oxygenase while growing on a noncompetitive substrate (29,32,41). Perhaps more problematic is the t...

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Mutagenic and Oncogenic Effects of Chloromethanes, Chloroethanes and Halogenated Analogues of Vinyl Chloride

Cited by 24 publications

References 18 publications

Janibacter brevis sp. nov., a new trichloroethylene-degrading bacterium isolated from polluted environments.

Janibacter brevis sp. nov., a new trichloroethylene-degrading bacterium isolated from polluted environments.

In situbioremediation of trichloroethylene-contaminated water by a resting-cell methanotrophic microbial filter

Cytotoxicity Associated with Trichloroethylene Oxidation in Burkholderia cepacia G4

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