title: Chemistry of oxidation of polycyclic aromatic hydrocarbons by soil pseudomonads.
abstract: Rogoff, Martin H. (U.S. Bureau of Mines, Pittsburgh, Pa.). Oxidation of polycyclic aromatic hydrocarbons by soil pseudomonads. J. Bacteriol. 83:998-1004. 1962.-Substitution of phenanthrene by a methyl group at the 9-carbon blocks oxidation of the compound by a resting-cell suspension of a phenanthrene-grown soil pseudomonad. When 2-methylphenanthrene is provided, the oxidation rate is considerably higher; 3-methylphenanthrene is oxidized at a rate intermediate between the other two, even though the methyl group is attached to a carbon directly involved in ring splitting. Cells grown on naphthalene or anthracene oxidize phenanthrene at a much lower rate than cells grown with phenanthrene or 2-methylnaphthalene as the source of carbon. Naphthalene-grown cells also absorb less phenanthrene from aqueous solution than do their phenanthrene-grown counterparts. The data are in keeping with the hypothesis that polynuclear aromatic hydrocarbons attach to the relevant bacterial enzymes at carbon-carbon bonds of high electron density (K regions; localized double bonds), and that the ring-splitting reactions then occur at other bonds on the substrate molecule. The actual bond that undergoes fission is determined by the electronic and steric configurations of the enzyme-substrate complex. When linearly arranged aromatic compounds such as naphthalene or anthracene are attacked, attachment to an enzyme and ring splitting may take place on the same ring; angular aromatic compounds such as phenanthrene afford attachment to an enzyme at a bond in a ring other than the one containing the ring-splitting site.
mesh_terms: D000873:Anthracenes; D006838:Hydrocarbons / Q000378:metabolism*; D009281:Naphthalenes; D010084:Oxidation-Reduction; D010616:Phenanthrenes; D011084:Polycyclic Aromatic Hydrocarbons; D011549:Pseudomonas / Q000378:metabolism*; D012987:Soil
chemical_list: D000873:Anthracenes; D006838:Hydrocarbons; D009281:Naphthalenes; D010616:Phenanthrenes; D011084:Polycyclic Aromatic Hydrocarbons; D012987:Soil; C031721:naphthalene; C109834:2-methylphenanthrene; C031181:phenanthrene; C034020:anthracene; C027384:2-methylnaphthalene
keywords: HYDROCARBONS/metabolism; PSEUDOMONAS/metabolism