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(→‎Ligninolytic fungi)
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* fungi의  난분해성 물질(인공적으로 만들어진 유기화합물) 을 무해한 (탄산가스,메탄,수분,바이오가스 등)
+
= Mycoremediation =
−
 
+
Mycoremediation is a process of using fungi to degrade or detoxify contaminants in the environment.mycoremediation is actively investigated in these days as a potent bioremediation tool. For example, brown rot fungi can absorb heavy metals by chelating with oxalic acids while white rot fungi can degrade phenolic compounds (e.g dyes) from wastewater.
−
물질로 분해하고 ,안정적인 물질로 변화  시켜 본래의 물질보다 단순한구조로 만드는 metabolism 을 이용한 환경 정화 기술
+
Some fungi have diverse abilities to degrage or modify environmental pollutants. The low specificity of fungal enzymes and their independence from using pollutants as a growth substrate make these fungi well suited for bioremeidation processes.
−
 
+
−
 
+
−
 
+
 
*Materials for Fungal Biodegradation and Biodeterioration
 
*Materials for Fungal Biodegradation and Biodeterioration
  
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−
*[[enzymes]]
+
{{#switchtablink:Second section header|Click here to go to the next tab...}}
  
 +
= habitats of fungi =
 +
<div style="float:right;width:32%;margin-bottom:2px;">
 +
Fungi in the environment can exist as terrestrial and aquatic saprobes, yeasts, symbiotic partners of lichens, and mycorrhizal symbionts associated with plant roots. They can form ectomycorrhizal and endomycorrhizal associations and can influence soil structure (by enmeshment of particles), soil chemistry (by excretion of acids, for example) and plant growth (through the mobilization and provision of nutrients in exchange for photosynthetic assimilates). Saprotrophic fungi adapted to water-unsaturated soil or aqueous environments can propagate through spores adapted to dispersal through the atmosphere or water, respectively. Growing hyphae explore food sources by deploying extracellular enzymes (exoenzymes).
 +
</div>
  
−
=Ligninolytic fungi =
 
  
−
pollutants : PAHs , benzene/toluene/ethyl benzene/xylene (BTEX) ,synthetic substituted aromatics
+
[[File:Fungi fig.jpg|none|thumb|600px|'''Typical habitats of terrestrial and aquatic fungi, and some of their ecological features.'''
  
−
*PAHs는 2개 이상의 benzene ring 을 가진 화합물로써 , 용해 되지 않고, 안정적인 물질이다 .
+
From the following article:
  
−
:PAHs의 분해할수 있는 미생물은 산소를 ring 에 삽입하여 PAHs 의 용해도와 화학반응성을 높여 분해 할수 있다.
+
Untapped potential: exploiting fungi in bioremediation of hazardous chemicals
  
−
:2개 이상의 고리를 가지고 있는 PAHs는 물에 불용성의 물질이기 때문에 세포안으로 쉽게 들어올수 없어
+
Hauke Harms, Dietmar Schlosser & Lukas Y. Wick
  
−
:cytochrome p450 enzyme이나 dioxygense (bacteria)와 같은 intracellular enzyme 이 반응을 일으켜 분해 시킬수가 없다 .
+
Nature Reviews Microbiology 9, 177-192 (March 2011)
  
−
:'white rot' basidiomycetous fungi 는 extracellular enzyme system 을 가지고 있어 PAHs를 효과적으로 분해 할수 있다 .
+
doi:10.1038/nrmicro2519
 +
]]
  
−
:extracellular enzyme 은 [[lignin depolymerization]] , [[demethoxylation]] , [[decarboxylation]] , [[decarboxylation]] , [[hydroxylation]] 과
+
= Polutions in environment=
 +
[[File:Polution.png|none|thumb|650px|Polutions in environment]]
 +
==Ligninolytic fungi ==
  
−
:aromatic ring opening 을 촉매 하며, 위반응들의 대부분은 oxigen radical 을 만들어 오염물질 을 공격하여 분해 하는 작용을 진행 한다.
+
PAHs , benzene/toluene/ethyl benzene/xylene (BTEX) ,synthetic substituted aromatics
  
−
== white rot fungi  ==
+
*[[Polycyclic Aromatic Hydrocarbons ]]
  
−
*Lignin 을 분해 하는 white rot fungi
+
*[[Dioxins ]]
  
−
Lignin 은 매우 복합성의 물질로 두가지 이상의 단량체가 결합한 복합체 ( phenylpropanoid 단량체 가 다양한 C-C 와 C-O 결합 으로 무질서 하게 결합
+
*[[Polychlorinated biphenyls ]]
  
−
된 물질) 이며 L - form 과 D- form 으로 존재하는 구조 이성질체 로  미생물에 의해 분해 되기 어려운 물질중의 하나 이다.
+
*[[Cholorophenols ]]
  
−
따라서 미생물이 lignin 을 분해하기 위해선 특이성과 구조선택 특이성 이 없는 mechanism 을 필요로 한다.
 
  
−
white rot fungi  는  non-specific enzyme system을 가지고 있어,lignin 뿐 아니라 다양한 halogenated / non halogenated aromatic compound
+
== KUC fungi  ==
  
−
몇가지 non aromatic organopollutant 를 분해 할수있다.
+
*[[Anthracene]]
−
+
*[[Phenanthrene]]
 +
*[[Fluoranthene]]
 +
*[[Pyrene]]
  
−
*Lignin degradation system
 
  
−
주요 효소들은 extracellular enzyme 으로 많은 세포 안으로 바로 들어올수 없는 non polar / non -soluble toxic compounds 에 접근하여
+
[[File:Organic chemicals.jpg|none|thumb|650px|
  
−
bioremediation 을 개시 하며 , 높은 독성물질의 농도 에도 fungi 가 버틸수 있도록 한다는것으로 알려져 있다 .
 
  
−
-Lgnin modifying enzyme (LMEs)의 주요 효소
+
From the following article:
  
−
*[[lignin peroxidase]]
+
Untapped potential: exploiting fungi in bioremediation of hazardous chemicals
−
*[[Manganese peroxidase | Mn-dependent peroxidase]]
+
−
*[[laccase]]
+
  
−
=== 오염물질  ===
+
Hauke Harms, Dietmar Schlosser & Lukas Y. Wick
  
−
*[[Polycyclic Aromatic Hydrocarbons ]]
+
Nature Reviews Microbiology 9, 177-192 (March 2011)
  
−
*[[Dioxins ]]
+
doi:10.1038/nrmicro2519
 +
]]
  
−
*[[Polychlorinated biphenyls ]]
+
= Enzymes for mycormediation =
 +
__NOTOC__
  
−
*[[Cholorophenols ]]
+
==Laccases (EC 1.10.3.2) ==
 +
Fungal taxa : Ascomycota and Basidiomycota
 +
 
 +
Localization and occurrence: Extracellular
 +
 
 +
Reaction mechanism: O2-dependent one-electron oxidation of organic compounds
 +
 
 +
::• Redox potential of around 0.4–0.8 V
 +
::• Direct oxidation of various phenols, aromatic amines and anthraquinone dyes
 +
::• A wide range of pollutants oxidized in the presence of natural and synthetic redox mediators
 +
::• Activity mostly in the acidic and rarely in the neutral or alkaline pH range
 +
 
 +
*[[Laccase | Laccase]]
 +
 
 +
 
 +
== Tyrosinases (EC 1.14.18.1) ==
 +
 
 +
Fungal taxa : Ascomycota, Basidiomycota and Mucoromycotina
 +
 
 +
Localization and occurrence: Sometimes extracellular but mainly intracellular
 +
 
 +
Reaction mechanism:
 +
::• O2-dependent hydroxylation of monophenols to o-diphenols (cresolase activity)
 +
::• Oxidation of o-diphenols to catechols (catecholase activity)
 +
 
 +
::• Oxidation of various phenols, including those that are highly chlorinated
 +
::• Activity from the acidic to the alkaline pH range
 +
 
 +
== Lignin peroxidases (EC 1.11.1.14) ==
 +
 
 +
Fungal taxa : Basidiomycota
 +
 
 +
Localization and occurrence: Extracellular
 +
 
 +
Reaction mechanism:
 +
 
 +
::• H2O2-dependent one-electron oxidation of aromatic compounds
 +
 
 +
::• Redox potential of 1.4–1.5 V
 +
::• Direct oxidation of various aromatics with high redox potentials, but rapid inactivation during oxidation of phenols
 +
::• Direct oxidation of PAHs with an ionization potential of ≤7.55 eV
 +
::• Extended substrate range (including dyes with high redox potentials and phenols) in the presence of the redox mediator veratryl alcohol
 +
::• Activity in the acidic pH range
 +
 
 +
*[[Lignin peroxidase |Lignin peroxidase (LiP)]]
 +
 
 +
== Manganese peroxidases (EC 1.11.1.13) ==
 +
 
 +
Fungal taxa : Basidiomycota
 +
 
 +
Localization and occurrence: Extracellular
 +
 
 +
Reaction mechanism:
 +
::• H2O2-dependent one-electron oxidation of Mn2+ to Mn3+, which subsequently oxidizes organic compounds
 +
 
 +
::• Redox potential of 1.0–1.2 V
 +
::• Mn3+-mediated oxidation of various phenols and aromatic amines
 +
::• Extended substrate range in the presence of co-oxidants (organic SH-containing compounds, unsaturated fatty acids and their derivatives)
 +
::• Activity in the acidic pH range
 +
 
 +
*[[Manganese peroxidase | Manganese peroxidase (MnP)]]
 +
 
 +
 
 +
==Versatile peroxidases (EC 1.11.1.16)==
 +
 
 +
Fungal taxa :Basidiomycota
 +
 
 +
Localization and occurrence:Extracellular
 +
 
 +
Reaction mechanism:
 +
::• H2O2-dependent direct one-electron oxidation of aromatic compounds
 +
::• H2O2-dependent one-electron oxidation of Mn2+ to Mn3+, which subsequently oxidizes organic compounds
 +
 
 +
::• Redox potential of around 1.4–1.5 V
 +
::• Direct oxidation of phenols and aromatics with high redox potentials, including dyes
 +
::• Mn3+-dependent reactions as for manganese peroxidase
 +
::• Activity in the acidic pH range
 +
 
 +
 
 +
 
 +
 
 +
 
 +
==Coprinopsis cinerea peroxidase (EC 1.11.1.7)==
 +
Fungal taxa :Basidiomycota
 +
 
 +
Localization and occurrence:Extracellular
 +
 
 +
Reaction mechanism:
 +
::• H2O2-dependent one-electron oxidation of aromatic compounds
 +
 
 +
::• Redox potential of around 0.9–1.1 V
 +
::• Direct oxidation of phenols and dyes with low redox potentials
 +
::• Activity from the acidic to the alkaline pH range
 +
 
 +
 
 +
 
 +
 
 +
==Dye-decolorizing peroxidases (EC 1.11.1.x) ==
 +
 
 +
Fungal taxa :Basidiomycota
 +
 
 +
Localization and occurrence: Extracellular
 +
 
 +
Reaction mechanism:
 +
::• H2O2-dependent one-electron oxidation of organic compounds
 +
::• Additional hydrolysing activity
 +
 
 +
::• Redox potential of around 1.2–1.5 V
 +
::• Oxidation of anthraquinone dyes with high redox potentials (only rarely oxidized by other peroxidases)
 +
::• Highly stable at high pressure, high temperature and very low pH
 +
::• Activity in the acidic pH range
 +
 
 +
 
 +
==Caldariomyces fumago haem–thiolate chloroperoxidase (EC 1.11.1.10)==
 +
 
 +
Fungal taxa :Ascomycota
 +
 
 +
Localization and occurrence:Extracellular
 +
 
 +
Reaction mechanism:
 +
::• H2O2-dependent halogenation of organic compounds in the presence of halides (one-electron transfer)
 +
::• H2O2-dependent one-electron oxidations of phenols and anilines in the absence of halides
 +
::• H2O2-dependent peroxygenation (two-electron oxidation), leading to epoxidation of (cyclo)alkenes, hydroxylation of benzylic carbon and sulphoxidation of S-containing organic compounds
 +
 
 +
::• Redox potential not known
 +
::• No activity on non-substituted aromatic rings and n-alkanes
 +
::• Activity in the acidic pH range
 +
 
 +
 
 +
 
 +
 
 +
==Haem–thiolate peroxygenases ==
 +
 
 +
Fungal taxa : Basidiomycota
 +
 
 +
Localization and occurrence: Extracellular
 +
 
 +
Reaction mechanism:
 +
::• H2O2-dependent peroxygenation of aromatic, aliphatic and heterocyclic compounds, leading to aromatic and alkylic carbon hydroxylation, double-bond epoxidation, ether cleavage, sulphoxidation or N-oxidation reactions (depending on the substrate);
 +
::• H2O2-dependent one-electron abstractions from phenols;
 +
::• H2O2-dependent bromination of organic substrates
 +
 
 +
::• Redox potential not known
 +
::• Peroxygenation of various monoaromatic to polyaromatic pollutants, including PAHs, dibenzofuran, and monohydroxylated and polyhydroxylated products
 +
::• Ether bond cleavage between aromatic and aliphatic parts of molecules and in alicyclic and aliphatic ethers (for example, MTBE)
 +
::• Activity from the acidic to the alkaline pH range
 +
 
 +
==Cytochrome P450 monooxygenases ==
 +
 
 +
Fungal taxa : Ascomycota, Basidiomycota, Mucoromycotina and Chytridiomycota
 +
 
 +
Localization and occurrence: Cell bound
 +
 
 +
Reaction mechanism:
 +
 
 +
::• Incorporation of a single atom from O2 into a substrate molecule, with concomitant reduction of the other atom to H2O
 +
 
 +
::• Epoxidation and hydroxylation of aromatic or aliphatic structures of many pollutants, including PAHs, PCDDs, alkanes and alkyl-substituted aromatics
 +
 
 +
 
 +
 
 +
==Phenol 2-monooxygenases (EC 1.14.13.7) ==
 +
 
 +
Fungal taxa : Ascomycota and Basidiomycota
 +
 
 +
Localization and occurrence: Cell bound
 +
 
 +
 
 +
Reaction mechanism:
 +
::• Incorporation of a single atom from O2 into a substrate molecule, with concomitant reduction of the other atom to H2O
 +
 
 +
::• Ortho-hydroxlyation of various (halo)phenols to the corresponding catechols
 +
 
 +
 
 +
 
 +
== Nitroreductases ==
 +
 
 +
Fungal taxa : Ascomycota and Basidiomycota and Mucoromycotina
 +
 
 +
Localization and occurrence: Cell bound
 +
 
 +
Reaction mechanism:
 +
 
 +
::• NAD(P)H-dependent reduction of nitroaromatics to hydroxylamino and amino(nitro) compounds, and of nitro functional groups of N-containing heterocycles
  
 +
::• Reduction of TNT to hydroxylamino-dinitrotoluene and amino-dinitrotoluenes
 +
::• Formation of mononitroso derivatives and ring cleavage products from cyclic nitramine explosives
 +
::• Widespread among fungi
  
  
  
 +
== Quinone reductases ==
  
 +
Fungal taxa :Basidiomycota
  
 +
Localization and occurrence: Cell bound
  
  
 +
Reaction mechanism:
 +
::• NAD(P)H-dependent reduction of quinones
  
 +
::• Functions in quinone detoxification, in the conversion of quinones arising from extracellular pollutant oxidation into substrates for extracellular and intracellular oxidoreductases, and in pollutant attack by hydroxyl radicals arising from quinone redox cycling
 +
::• Occurrence in white-rot and brown-rot basidiomycetes
  
  
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 +
==Reductive dehalogenases ==
  
 +
Fungal taxa : Basidiomycota and perhaps Ascomycota
  
 +
Localization and occurrence:  Cell bound
  
 +
Reaction mechanism:
 +
::• Two-component system comprising a membrane-bound glutathione S-transferase that produces glutathionyl conjugates with concomitant chlorine removal, and a soluble glutathione conjugate reductase that releases reductively dechlorinated compounds
  
 +
::• Reductive dechlorination of chlorohydroquinones arising from chlorophenol degradation and of diphenyl ether herbicides (basiodiomycetes)
 +
::• Perhaps responsible for reductive dechlorination of chlorocatechols arising from PCDD degradation (ascomycetes)
  
  
−
*[[Petroleum Hydrocarbons ]]
+
==Miscellaneous transferases ==
  
−
*[[Polychlorinated Biphenyls and Dioxins ]]
+
Fungal taxa : Ascomycota, Basidiomycota and Mucoromycotina
  
−
*[[Pesticides ]]
+
Localization and occurrence:Cell bound
  
−
*[[Phenols, Chlorophenols, and Pentachlorophenol ]]
+
Reaction mechanism:
 +
::• Formation of glucoside, glucuronide, xyloside, sulphate or methyl conjugates from hydroxylated compounds
  
 +
::• Phase II enzymes are prominent in fungal PAH metabolism but also act on other pollutants
 +
::• Widespread among fungi
  
−
*[[Pulp and Paper Mill Effluents]]
+
=Reference =
  
−
*[[ Heavy Metals ]]
+
Untapped potential: exploiting fungi in bioremediation of hazardous chemicals
 +
Hauke Harms, Dietmar Schlosser & Lukas Y. Wick
 +
Nature Reviews Microbiology 9, 177-192 (March 2011)
 +
doi:10.1038/nrmicro2519
  
−
*[[Dyes]]
+
<headertabs/>

Latest revision as of 17:32, 5 April 2013

[edit]

Mycoremediation is a process of using fungi to degrade or detoxify contaminants in the environment.mycoremediation is actively investigated in these days as a potent bioremediation tool. For example, brown rot fungi can absorb heavy metals by chelating with oxalic acids while white rot fungi can degrade phenolic compounds (e.g dyes) from wastewater. Some fungi have diverse abilities to degrage or modify environmental pollutants. The low specificity of fungal enzymes and their independence from using pollutants as a growth substrate make these fungi well suited for bioremeidation processes.

  • Materials for Fungal Biodegradation and Biodeterioration
Wood Plastics Library materials
Wooden artifacts Wool Wall paintings
Stored paper Wrapping papers Electroinsulating materials
Textiles Glass surfaces Coal
Leather Concrete Ground waste rubber materials


Click here to go to the next tab...

Fungi in the environment can exist as terrestrial and aquatic saprobes, yeasts, symbiotic partners of lichens, and mycorrhizal symbionts associated with plant roots. They can form ectomycorrhizal and endomycorrhizal associations and can influence soil structure (by enmeshment of particles), soil chemistry (by excretion of acids, for example) and plant growth (through the mobilization and provision of nutrients in exchange for photosynthetic assimilates). Saprotrophic fungi adapted to water-unsaturated soil or aqueous environments can propagate through spores adapted to dispersal through the atmosphere or water, respectively. Growing hyphae explore food sources by deploying extracellular enzymes (exoenzymes).


Typical habitats of terrestrial and aquatic fungi, and some of their ecological features. From the following article: Untapped potential: exploiting fungi in bioremediation of hazardous chemicals Hauke Harms, Dietmar Schlosser & Lukas Y. Wick Nature Reviews Microbiology 9, 177-192 (March 2011) doi:10.1038/nrmicro2519

Polutions in environment

[edit] Ligninolytic fungi

PAHs , benzene/toluene/ethyl benzene/xylene (BTEX) ,synthetic substituted aromatics


[edit] KUC fungi


From the following article: Untapped potential: exploiting fungi in bioremediation of hazardous chemicals Hauke Harms, Dietmar Schlosser & Lukas Y. Wick Nature Reviews Microbiology 9, 177-192 (March 2011) doi:10.1038/nrmicro2519

[edit] Laccases (EC 1.10.3.2)

Fungal taxa : Ascomycota and Basidiomycota

Localization and occurrence: Extracellular

Reaction mechanism: O2-dependent one-electron oxidation of organic compounds

• Redox potential of around 0.4–0.8 V
• Direct oxidation of various phenols, aromatic amines and anthraquinone dyes
• A wide range of pollutants oxidized in the presence of natural and synthetic redox mediators
• Activity mostly in the acidic and rarely in the neutral or alkaline pH range


[edit] Tyrosinases (EC 1.14.18.1)

Fungal taxa : Ascomycota, Basidiomycota and Mucoromycotina

Localization and occurrence: Sometimes extracellular but mainly intracellular

Reaction mechanism:

• O2-dependent hydroxylation of monophenols to o-diphenols (cresolase activity)
• Oxidation of o-diphenols to catechols (catecholase activity)
• Oxidation of various phenols, including those that are highly chlorinated
• Activity from the acidic to the alkaline pH range

[edit] Lignin peroxidases (EC 1.11.1.14)

Fungal taxa : Basidiomycota

Localization and occurrence: Extracellular

Reaction mechanism:

• H2O2-dependent one-electron oxidation of aromatic compounds
• Redox potential of 1.4–1.5 V
• Direct oxidation of various aromatics with high redox potentials, but rapid inactivation during oxidation of phenols
• Direct oxidation of PAHs with an ionization potential of ≤7.55 eV
• Extended substrate range (including dyes with high redox potentials and phenols) in the presence of the redox mediator veratryl alcohol
• Activity in the acidic pH range

[edit] Manganese peroxidases (EC 1.11.1.13)

Fungal taxa : Basidiomycota

Localization and occurrence: Extracellular

Reaction mechanism:

• H2O2-dependent one-electron oxidation of Mn2+ to Mn3+, which subsequently oxidizes organic compounds
• Redox potential of 1.0–1.2 V
• Mn3+-mediated oxidation of various phenols and aromatic amines
• Extended substrate range in the presence of co-oxidants (organic SH-containing compounds, unsaturated fatty acids and their derivatives)
• Activity in the acidic pH range


[edit] Versatile peroxidases (EC 1.11.1.16)

Fungal taxa :Basidiomycota

Localization and occurrence:Extracellular

Reaction mechanism:

• H2O2-dependent direct one-electron oxidation of aromatic compounds
• H2O2-dependent one-electron oxidation of Mn2+ to Mn3+, which subsequently oxidizes organic compounds
• Redox potential of around 1.4–1.5 V
• Direct oxidation of phenols and aromatics with high redox potentials, including dyes
• Mn3+-dependent reactions as for manganese peroxidase
• Activity in the acidic pH range



[edit] Coprinopsis cinerea peroxidase (EC 1.11.1.7)

Fungal taxa :Basidiomycota

Localization and occurrence:Extracellular

Reaction mechanism:

• H2O2-dependent one-electron oxidation of aromatic compounds
• Redox potential of around 0.9–1.1 V
• Direct oxidation of phenols and dyes with low redox potentials
• Activity from the acidic to the alkaline pH range



[edit] Dye-decolorizing peroxidases (EC 1.11.1.x)

Fungal taxa :Basidiomycota

Localization and occurrence: Extracellular

Reaction mechanism:

• H2O2-dependent one-electron oxidation of organic compounds
• Additional hydrolysing activity
• Redox potential of around 1.2–1.5 V
• Oxidation of anthraquinone dyes with high redox potentials (only rarely oxidized by other peroxidases)
• Highly stable at high pressure, high temperature and very low pH
• Activity in the acidic pH range


[edit] Caldariomyces fumago haem–thiolate chloroperoxidase (EC 1.11.1.10)

Fungal taxa :Ascomycota

Localization and occurrence:Extracellular

Reaction mechanism:

• H2O2-dependent halogenation of organic compounds in the presence of halides (one-electron transfer)
• H2O2-dependent one-electron oxidations of phenols and anilines in the absence of halides
• H2O2-dependent peroxygenation (two-electron oxidation), leading to epoxidation of (cyclo)alkenes, hydroxylation of benzylic carbon and sulphoxidation of S-containing organic compounds
• Redox potential not known
• No activity on non-substituted aromatic rings and n-alkanes
• Activity in the acidic pH range



[edit] Haem–thiolate peroxygenases

Fungal taxa : Basidiomycota

Localization and occurrence: Extracellular

Reaction mechanism:

• H2O2-dependent peroxygenation of aromatic, aliphatic and heterocyclic compounds, leading to aromatic and alkylic carbon hydroxylation, double-bond epoxidation, ether cleavage, sulphoxidation or N-oxidation reactions (depending on the substrate);
• H2O2-dependent one-electron abstractions from phenols;
• H2O2-dependent bromination of organic substrates
• Redox potential not known
• Peroxygenation of various monoaromatic to polyaromatic pollutants, including PAHs, dibenzofuran, and monohydroxylated and polyhydroxylated products
• Ether bond cleavage between aromatic and aliphatic parts of molecules and in alicyclic and aliphatic ethers (for example, MTBE)
• Activity from the acidic to the alkaline pH range

[edit] Cytochrome P450 monooxygenases

Fungal taxa : Ascomycota, Basidiomycota, Mucoromycotina and Chytridiomycota

Localization and occurrence: Cell bound

Reaction mechanism:

• Incorporation of a single atom from O2 into a substrate molecule, with concomitant reduction of the other atom to H2O
• Epoxidation and hydroxylation of aromatic or aliphatic structures of many pollutants, including PAHs, PCDDs, alkanes and alkyl-substituted aromatics


[edit] Phenol 2-monooxygenases (EC 1.14.13.7)

Fungal taxa : Ascomycota and Basidiomycota

Localization and occurrence: Cell bound


Reaction mechanism:

• Incorporation of a single atom from O2 into a substrate molecule, with concomitant reduction of the other atom to H2O
• Ortho-hydroxlyation of various (halo)phenols to the corresponding catechols


[edit] Nitroreductases

Fungal taxa : Ascomycota and Basidiomycota and Mucoromycotina

Localization and occurrence: Cell bound

Reaction mechanism:

• NAD(P)H-dependent reduction of nitroaromatics to hydroxylamino and amino(nitro) compounds, and of nitro functional groups of N-containing heterocycles
• Reduction of TNT to hydroxylamino-dinitrotoluene and amino-dinitrotoluenes
• Formation of mononitroso derivatives and ring cleavage products from cyclic nitramine explosives
• Widespread among fungi


[edit] Quinone reductases

Fungal taxa :Basidiomycota

Localization and occurrence: Cell bound


Reaction mechanism:

• NAD(P)H-dependent reduction of quinones
• Functions in quinone detoxification, in the conversion of quinones arising from extracellular pollutant oxidation into substrates for extracellular and intracellular oxidoreductases, and in pollutant attack by hydroxyl radicals arising from quinone redox cycling
• Occurrence in white-rot and brown-rot basidiomycetes



[edit] Reductive dehalogenases

Fungal taxa : Basidiomycota and perhaps Ascomycota

Localization and occurrence: Cell bound

Reaction mechanism:

• Two-component system comprising a membrane-bound glutathione S-transferase that produces glutathionyl conjugates with concomitant chlorine removal, and a soluble glutathione conjugate reductase that releases reductively dechlorinated compounds
• Reductive dechlorination of chlorohydroquinones arising from chlorophenol degradation and of diphenyl ether herbicides (basiodiomycetes)
• Perhaps responsible for reductive dechlorination of chlorocatechols arising from PCDD degradation (ascomycetes)


[edit] Miscellaneous transferases

Fungal taxa : Ascomycota, Basidiomycota and Mucoromycotina

Localization and occurrence:Cell bound

Reaction mechanism:

• Formation of glucoside, glucuronide, xyloside, sulphate or methyl conjugates from hydroxylated compounds
• Phase II enzymes are prominent in fungal PAH metabolism but also act on other pollutants
• Widespread among fungi

Untapped potential: exploiting fungi in bioremediation of hazardous chemicals Hauke Harms, Dietmar Schlosser & Lukas Y. Wick Nature Reviews Microbiology 9, 177-192 (March 2011) doi:10.1038/nrmicro2519

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