title: Identification of metabolites from phenanthrene oxidation by phenoloxidases and dioxygenases of Polyporus sp. S133.
abstract: Phenanthrene degradation by Polyporus sp. S133, a new phenanthrene-degrading strain, was investigated in this work. The analysis of degradation was performed by calculation of the remaining phenanthrene by gas chromatography-mass spectrometry. When cells were grown in phenanthrene culture after 92 h, all but 200 and 250 mg/l of the phenanthrene had been degraded. New metabolic pathways of phenanthrene and a better understanding of the phenoloxidases and dioxygenase mechanism involved in degradation of phenanthrene were explored in this research. The mechanism of degradation was determined through identification of the several metabolites; 9,10-phenanthrenequinone, 2,2'-diphenic acid, salicylic acid, and catechol. 9,10-Oxidation and ring cleavage to give 9,10-phenanthrenequinone is the major fate of phenanthrene in ligninolytic Polyporus sp. S133. The identification of 2,2'-diphenic acid in culture extracts indicates that phenanthrene was initially attacked through dioxigenation at C9 and C10 to give cis-9,10-dihydrodiol. Dehydrogenation of phenanthrene-cis-9,10-dihydrodiol to produce the corresponding diol, followed by ortho-cleavage of the oxygenated ring, produced 2,2'-diphenic acid. Several enzymes (manganese peroxidase, lignin peroxidase, laccase, 1,2-dioxygenase, and 2,3-dioxygenase) produced by Polyporus sp. S133 was detected during the incubation. The highest level of activity was shown at 92 h of culture.
authors.affiliation: Institute of Environmental and Water Research Management, Universiti Teknologi Malaysia, Skudai, Johor, Malaysia. hadibarata@utm.my
authors.forename: Tony
authors.initials: T
authors.lastname: Hadibarata
authors.forename: Sanro
authors.initials: S
authors.lastname: Tachibana
authors.forename: Muhamad
authors.initials: M
authors.lastname: Askari
mesh_terms: D001711:Biotransformation; D001713:Biphenyl Compounds / Q000032:analysis; D002396:Catechols / Q000032:analysis; D049308:Dioxygenases / Q000378:metabolism*; D008401:Gas Chromatography-Mass Spectrometry; D014442:Monophenol Monooxygenase / Q000378:metabolism*; D010084:Oxidation-Reduction; D010616:Phenanthrenes / Q000032:analysis / Q000378:metabolism*; D055492:Polyporus / Q000201:enzymology* / Q000378:metabolism*; D020156:Salicylic Acid / Q000032:analysis; D013997:Time Factors
chemical_list: D001713:Biphenyl Compounds; D002396:Catechols; D010616:Phenanthrenes; C005399:9,10-phenanthrenequinone; C031181:phenanthrene; D049308:Dioxygenases; D014442:Monophenol Monooxygenase; C034221:catechol; D020156:Salicylic Acid; C039204:diphenic acid