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The Mechanism. Fungi have ligninase and cellulase enzymes that break down woody materials. This allows fungi to get the needed carbon and energy they require for growth.These enzymes are non-specific, meaning they can act on substrates like environmental pollutants.. Physical Mechanism. Hyphae allo
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1. Fungi for Bioremediation Julie Quinn
ESM 219 actinomycetesactinomycetes
2. The Mechanism Fungi have ligninase and cellulase enzymes that break down woody materials. This allows fungi to get the needed carbon and energy they require for growth.
These enzymes are non-specific, meaning they can act on substrates like environmental pollutants. LiP and MnP (ligninase manganese peroxidase) produce free radicals which have a high redox potential, with optimal function at pH =3
Laccase has the ability to oxidize phenolic cmpds extracellularly.
Hyphae allow fungi to increase reaction surface area and get to the pollutant
LiP and MnP (ligninase manganese peroxidase) produce free radicals which have a high redox potential, with optimal function at pH =3
Laccase has the ability to oxidize phenolic cmpds extracellularly.
Hyphae allow fungi to increase reaction surface area and get to the pollutant
3. Physical Mechanism Hyphae allow fungi to expand their surface area, making it easier to contact the pollutant.
Extracellular enzymes can then go to work.
4. Degradation of Organopollutants Phanerochaete chrysosporium, white rot fungi, acts to break down pollutants by adding an -OH group.
Hydroxilating makes the compound more polar.
Detoxification by hydroxilation (add -OH group) and excretion is standard for xenobiotic detoxification. Fungi can do this to pollutants too.Detoxification by hydroxilation (add -OH group) and excretion is standard for xenobiotic detoxification. Fungi can do this to pollutants too.
5. Pleurotos ostreatus laccase degradation of OP pesticides and nerve agents Organophosphorus pesticides and nerve agentsOrganophosphorus pesticides and nerve agents
6. Hebeloma crustuliniforme Fungi used in conjunction with the plant to remediate atrazine. Introduce fungi w/ host plant gives it better potential for successful survival.
Atrazine is a widely used herbicide.
Introduce fungi w/ host plant gives it better potential for successful survival.
Atrazine is a widely used herbicide.
7. PCB degradation by white rot fungi PCB volatility, sorption on biological matrices, and xenobiotic extraction method were factors affecting remediation success. Drying the sample led to concentration different results.Drying the sample led to concentration different results.
8. Anthracene One mechanism to measure the degradation is by dye decolorization.
There was a high correlation between elimination of anthracene and Poly R-478 (dye) decolorization.
Interestingly, four strains were able to oxidize anthracene to anthraquinone even after HgCl2 poisoning. Polycyclic aromatic hydrocarbon PAH
Antracene used in dyes, wood preservatives, and insecticides
Explanation: HgCl2 killed cells without completely inhibiting extracellular enzymes involved in the oxidation.
Anthraquinone is a dead-end metabolite which can be easily degraded by bacteria. Polycyclic aromatic hydrocarbon PAH
Antracene used in dyes, wood preservatives, and insecticides
Explanation: HgCl2 killed cells without completely inhibiting extracellular enzymes involved in the oxidation.
Anthraquinone is a dead-end metabolite which can be easily degraded by bacteria.
9. Biodegradation of Nitro-substituted explosives Wood and litter decaying fungi have been shown to metabolize TNT, but only a few of the species tested to date have been able to mineralize it.
Problems: fungi have to compete with indigenous microflora, mineralization rate lower in soil than liquid medium, unclear biotransformation consequences. Biotransformation consequences for nitroaromatic cmpds results inn increased polarity, lower volatility, higher susceptibility to bind with soil matrix, further metabolism by other microbes.Biotransformation consequences for nitroaromatic cmpds results inn increased polarity, lower volatility, higher susceptibility to bind with soil matrix, further metabolism by other microbes.
10. DNT CO2 Oxidizing to get rid of nitro groups, adds OH (hydrolilates) LiP, MnP further oxidize until get final CO2 product.Oxidizing to get rid of nitro groups, adds OH (hydrolilates) LiP, MnP further oxidize until get final CO2 product.
11. Conclusions
Fungi can be used to reduce waste streams in agriculture, forestry, and paper industries.
Successful degradation of pollutants via non-specific enzymatic activity.
12. Questions?