Environmental Organic Chemistry Instructor: Jaeweon Cho

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Environmental Organic ChemistryInstructor
Jaeweon Cho
13th Week Class
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Outlines

• Biological medicated transformation
• Transformation vs. degradation
• Mineralization
• Microbial Ecology Enzymology
• Enzymes
• proteins
• catalysis lowering activation energy
• Goals
• understanding initiate xenobiotic
  bio-transformation
• understand which structures can be attacked

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Outlines

• Biotransformation or Degradation
• Delivery of Organics to Microorganisms
• Polar vs. non-polar
• size
• Enzyme
• More enzyme
• Effective enzyme
• Population of microorganisms metabolic
• Genetic points of view horizontal exchange of
  plasmid DNA

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• Some important concepts
• Conditions
• Oxic vs. anoxic
• Generally, aromatic vs. chlorinated compounds
• Metals presence metals-containing enzyme
• Consortia
• Even 7 bacteria
• Sometimes, inhibition e.g., suicide metabolites
• Plasmid DNA
• Horizontal exchange in consortia
• If beneficial, it is maintained otherwise, it is
  abandoned

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• Biochemical Points of View
• Hydrolysis
• Nucleophilic attacks
• Oxidation
• Electrophilic form of oxygen
• Reduction
• Nucleophilic form of hydride
• Reduced metals

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• Biochemical Points of View
• Hydrolysis
• Nucleophilic attacks
• Oxidation
• Electrophilic form of oxygen
• Reduction
• Nucleophilic form of hydride
• Reduced metals

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What are typical characteristics for Hydrolysis?
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• Hydrolysis
• De-halide by GSH enzyme
• Esters
• Serine (OH)
• Cysteine (SH)
• Zn-containing hydrolase

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• Hydrolysis
• De-halide by GSH enzyme
• Esters
• Serine (OH)
• Cysteine (SH)
• Zn-containing hydrolase

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• Hydrolysis
• De-halide by GSH enzyme
• Esters
• Serine (OH)
• Cysteine (SH)
• Zn-containing hydrolase

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Serine (OH)
Histidine Aspartic acid
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• Hydrolysis
• De-halide by GSH enzyme
• Esters
• Serine (OH)
• Cysteine (SH)
• Zn-containing hydrolase

glutamate
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• Biochemical Points of View
• Hydrolysis
• Nucleophilic attacks
• Oxidation
• Electrophilic form of oxygen
• Reduction
• Nucleophilic form of hydride
• Reduced metals

O2
Reactive Oxidants
Enzymes (oxygenases) with metals and coenzymes
(NADH)
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dioxygenase
Monooxygenase
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• Biochemical Points of View
• Hydrolysis
• Nucleophilic attacks
• Oxidation
• Electrophilic form of oxygen
• Reduction
• Nucleophilic form of hydride
• Reduced metals

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NADH
FADH
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Some microorganisms are capable of using
halogenated compounds as terminal electron
acceptors e.g., they use tetrachloroethene to
breath instead of O2, NO3-, SO42-. Please recall
that reductive biotransformation (dehalogenation)
is favored under anoxic condition! in Microbial
Ecology.
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