L12 : Extremophile Applications Flashcards
(40 cards)
What are challenges in isolating and study extremophiles in regards to microbes?
- Mimic natural environment
- Avoid cross contamination (eg. horizontal gene transfer)
- Sample preservation
- Design suitable experimental protocols
- Maintain cell morphology under microscope (same conditions as in nature)
- Good choice of expression hosts
What are challenges in studying extremophiles in regard to humans?
- Access remote locations
- Cost
- Right experiment (storage, measurements)
- Work under harsh conditions
- Human health hazard due to toxicity
- Regular compliance for work in protected environments
- Limited knowledge for experimental design and data analysis
What are the different areas of biotechnology?
Red: medicine, therapeutics, healthcare
White: manufacture, energy, sustainability
Grey: Environment, conservation, bioremediation, bioleaching
Green: plant, agriculture, food chain
Why remove heavy metals from the environment?
Due to toxicity
Able to extract and use
What are some conventional mitigation methods to remove heavy metals?
- Reverse osmosis
- Electrodialysis
- Ion exchange
- Filtration
- Adsorption
- Co-precipitation
What are 3 disadvantages of conventional methods?
- High cost
- Inability to treat large volumes
- Generation of large amounts of metal sludge
What are some characteristics and causes of environmental pollution?
- Mining industry
- Metal plating
- Paper production
- Printing and dyeing
Results in high temps, low pH, high salt
Opportunity for extremophiles
What is bioleaching?
Use of microorganisms to extract metals from ores due to ability to:
- Break down solid compounds
- Transform into soluble, extractable, and recoverable elements
Why are extremophiles important in bioleaching and metal recovery?
Extremophiles offer:
- Sustainability
- Energy efficiency
- Efficient processing (low grade ore processing)
Extremophile types and elements
What is waste water bioremediation?
Clean up polluted environment by degrading or neutralising contaminants
Eg. pesticides, heavy metals, industrial chemicals, oil spills
What is radiation bioremediation?
Some extremophiles have ability to accumulate and sequester radionuclides from environmental
- Immobilised within microbial biomass
How is radiation remediation used for strodium and why?
Closterium moniliferum detoxifies strodium-90 through reduction
- Similar in properties and atomic size to Ca (useful element)
- Chemical processes cannot separate elements
- Can infiltrate milk, bone (marrow), blood/tissue
- Difficult to clean (half life = 30y)
How is radiation remediation used for uranium and why?
Rhodopseudomonas palustris detoxifies uranium through reduction
- Highly chemotoxic
- Strong affinity for phosphates
What is hydrocarbon pollution and consequences?
Pollution from oil spill accidents or chronic contamination
- High salinity
- Extreme temps
- High acidity
- Hydrocarbon and byproduct toxicity)
Why is mitigation time sensitive?
Bioremediation is a better approach
Burning oil spills can release dangerous chemicals into ecosystem
Chemical remediation can prove dangerous to surrounding ecosystem
What are the 2 hydrocarbon pollution bioremediation approaches?
Biostimulation:
Add nutrients to stimulate oil-degrading metabolic pathways
Bioaugmentation:
Addition of known oil-degrading microorganisms in affected area
Why are extremophiles useful in hydrocarbon pollution bioremediation?
Provide stable and efficient enzymes
- Lipases, oxidases, hydrolases
How do thermophiles contribute to treatment of toxic pollution?
Using dissimilatory metal reduction (DMR)
- Electron donor (organic or inorganic compound)
- Electron acceptor (metal to be reduced)
- Occurs in anaerobic conditions
- Metal reducatase enzyme
Results in detoxification or immobilisation of metal
What is the effectiveness of dissimilatory metal reduction (DMR) dependent on?
- Electron donor/acceptor
- Environmental conditions (pH, temp)
- Concentration of metal in environment
What are glycoside hydrolases?
Enzymes that hydrolyse glycosidic bonds in complex carbohydrates (poly-, oligo- saccharides)
3 examples of extremophilic glycosidic hydrolases and products they can manufacture?
B-galactosidase from psychrophiles
- Hydrolyse lactose
- Lactose free dairy
Trehalose from halophiles
- Stabilisers/preservatives
- Vaccine, antibody, cosmetics
(Hemi)cellulases from thermophiles
- Hydrolyse cellulose, hemicellulose, lignin
- Biofuel)
What are biotechnological applications for extremophilic pigments?
- Cosmetics
- Food technology
- Pharmaceuticals
- Textile industry
- Leather tanning
- Paper production
What are the advantages of using extremophilic pigments?
- Safe for human use
- Probiotic activity (consumption)
- Efficient manipulation
- Cost effective
- Large scale production
- Easy maintenance/storage
