Related Experiment Video
Updated: Aug 3, 2026
15:19
Development of Sulfidogenic Sludge from Marine Sediments and Trichloroethylene Reduction in an Upflow Anaerobic Sludge Blanket Reactor
Published on: October 15, 2015
Fate of genetically-engineered bacteria in activated sludge microcosms
Schriftenreihe Des Vereins Fur Wasser-, Boden- Und Lufthygiene
|January 1, 1988
Summary
Genetically engineered microorganisms (GEMs) survived and degraded pollutants in microcosms, showing potential for environmental applications. Microcosm studies are crucial for predicting GEM behavior and ensuring safe, effective pollutant degradation.
Area of Science:
- Environmental Microbiology
- Biotechnology
- Genetic Engineering
Background:
- Pseudomonas sp. B13 and its genetically engineered derivatives (GEMs) were studied for their survival and pollutant degradation capabilities.
- Previous studies showed GEMs could degrade 3-chloro-benzoate (3CB) and 4-methyl-benzoate (4MB) in pure cultures.
Purpose of the Study:
- To assess the survival and pollutant degradation efficacy of GEMs in a complex activated sludge microcosm.
- To evaluate the impact of GEMs on the indigenous microbial community and the potential for horizontal gene transfer.
Main Methods:
- GEMs (Pseudomonas sp. B13 derivatives FR1 and FR1(pFRC20P)) were introduced into activated sludge microcosms.
- The survival of GEMs and their degradation of substituted benzoates (3CB, 4MB) were monitored.
- Impact on indigenous microbial populations and horizontal gene transfer were assessed.
Main Results:
- GEMs demonstrated significant survival (approx. 10(5) bacteria/ml) in the microcosm, contrary to expectations for long-term cultured strains.
- GEMs degraded low concentrations of substituted benzoates, though performance decreased with shock loads.
- GEM addition did not adversely affect indigenous microbial populations; it even offered protection against toxic pollutants.
Conclusions:
- Microcosm studies are valuable for predicting the environmental performance of GEMs.
- GEMs show promise for degrading environmental pollutants and offer a potential strategy for bioremediation.
- Horizontal gene transfer of a mobilizable plasmid occurred, potentially enhancing the ecosystem's pollutant degradation capacity.
Related Concept Videos
00:46Bioremediation
Bioremediation is the use of prokaryotes, fungi, or plants to remove pollutants from the environment. This process has been used to remove harmful toxins in groundwater as a byproduct of agricultural run-off and also to clean up oil spills.
01:30Environmental Applications of Microorganisms
Microorganisms play a pivotal role in maintaining ecosystem balance by recycling essential elements such as carbon, nitrogen, and phosphorus, as well as supporting processes like bioremediation, wastewater treatment, and biofuel production.Microbes in Elemental CyclesIn the carbon cycle, microorganisms decompose organic matter, releasing carbon dioxide via aerobic respiration. This carbon dioxide is subsequently used by photosynthetic organisms to synthesize organic compounds, closing the...
01:26Microbial Bioremediation of Hydrocarbons
Bioremediation is an environmentally sustainable process that employs living organisms—primarily microorganisms—to degrade or neutralize pollutants from contaminated environments. In oil spills and hydrocarbon pollution, bioremediation involves the use of hydrocarbon-degrading bacteria to transform toxic compounds into less harmful substances. This approach leverages natural microbial metabolic processes and is considered both cost-effective and ecologically favorable compared to physical or...
01:30Microbial Wastewater Treatment
Microbial communities in aquatic ecosystems play a key role in the natural breakdown of contaminants introduced through domestic and industrial effluents. Acting as biological catalysts, these microbes change and mineralize a wide range of organic and inorganic pollutants under different redox conditions.In oxygen-rich surface waters, aerobic heterotrophs lead organic matter breakdown, using oxygen as the terminal electron acceptor to efficiently oxidize substrates to carbon dioxide and water.
01:30Biological Treatment of Effluent and Waste Water
Biological wastewater treatment relies on the metabolic activity of microorganisms to remove pollutants from sewage. In modern treatment systems, this process is organized into sequential stages that progressively reduce solid material, dissolved organic matter, and microbial contamination. Each stage plays a distinct role in improving water quality and preparing the effluent for safe discharge or reuse.Primary and Secondary TreatmentPrimary treatment is a physical process that removes large...
01:28Microbial Bioremediation of Plastics
Polyethylene terephthalate (PET) is a synthetic polymer widely utilized in the packaging industry, particularly for bottles and containers. Due to its chemical stability and durability, PET accumulates in the environment, contributing significantly to plastic pollution. It comprises repeating units of terephthalic acid and ethylene glycol, resulting in a semi-crystalline structure that is resistant to natural degradation processes.A notable breakthrough in plastic biodegradation came with the...