Cloning and analysis of the genes for polycyclic aromatic hydrocarbon degradation.
Bacterial degradation of polycyclic aromatic hydrocarbons initially proceeds through monooxygenase or dioxygenase attack on the aromatic ring. The dihydroxylated compounds formed are substrates for ring cleavage and further catabolism to tricarboxylic acid cycle intermediates. A number of microbial strains, both gram positive and gram negative, have been isolated that have the metabolic capability to degrade polycyclic aromatic hydrocarbons to carbon dioxide and water. In addition, many of these strains have the ability to cometabolize structurally similar aromatic compounds that may not normally serve as metabolic inducers or as carbon sources. The genes from several of these strains have been cloned for the purpose of analyzing in more detail their structure and function. The cloned genes were used to determine the range of substrates that can be metabolized by the genetically encoded pathway. For instance, the cloned genes from Pseudomonas sp. XPW-2 placed in E. coli encoded for the oxidation of such polycyclic aromatic hydrocarbons as naphthalene, biphenyl, anthracene, phenanthrene, acenaphthylene, fluorene, fluoranthene, chrysene, and pyrene. The cloned genes were also used as genetic probes to determine the degree of homology, if any, there is between different microbial strains capable of degrading polycyclic aromatic hydrocarbons. These experiments indicated significant homology among the class of terrestrial naphthalene and phenanthrene-degrading strains. Nevertheless, little homology was seen across species lines or among strains capable of degrading higher molecular weight polycyclic aromatic hydrocarbons. This indicates that there is a diversity of genetically distinct pathways for polycyclic aromatic hydrocarbon degradation.
Center for Agricultural Molecular Biology, Rutgers University, New Brunswick, New Jersey 08903-0231.
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Zylstra
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Wang
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Kim
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Didolkar
D000429:Alcohol Oxidoreductases / Q000235:genetics; D001673:Biodegradation, Environmental; D003001:Cloning, Molecular; D049308:Dioxygenases; D005798:Genes, Bacterial; D007506:Iron-Sulfur Proteins; D009154:Mutation; D010088:Oxidoreductases; D044925:Oxidoreductases Acting on CH-CH Group Donors; D010105:Oxygenases / Q000235:genetics; D011083:Polycyclic Compounds / Q000737:chemistry / Q000378:metabolism*; D011548:Pseudomonadaceae / Q000235:genetics / Q000378:metabolism; D011549:Pseudomonas / Q000235:genetics / Q000378:metabolism; D015183:Restriction Mapping
D007506:Iron-Sulfur Proteins; D011083:Polycyclic Compounds; D010088:Oxidoreductases; D000429:Alcohol Oxidoreductases; C023125:dihydrodiol dehydrogenases; D010105:Oxygenases; D049308:Dioxygenases; C074272:2,3-dihydroxybiphenyl oxygenase; C074161:biphenyl-2,3-dioxygenase; D044925:Oxidoreductases Acting on CH-CH Group Donors; C116788:cis-1,2-dihydro-1,2-dihydroxynaphthalene dehydrogenase