Degradation of phenanthrene by Burkholderia sp. C3: initial 1,2- and 3,4-dioxygenation and meta- and ortho-cleavage of naphthalene-1,2-diol

Abstract

Burkholderia sp. C3 was isolated from a polycyclic aromatic hydrocarbon (PAH)-contaminated site in Hilo, Hawaii, USA, and studied for its degradation of phenanthrene as a sole carbon source. The initial 3,4-C dioxygenation was faster than 1,2-C dioxygenation in the first 3-day culture. However, 1-hydroxy-2-naphthoic acid derived from 3,4-C dioxygenation degraded much slower than 2-hydroxy-1-naphthoic acid derived from 1,2-C dioxygenation. Slow degradation of 1-hydroxy-2-naphthoic acid relative to 2-hydroxy-1-naphthoic acid may trigger 1,2-C dioxygenation faster after 3 days of culture. High concentrations of 5,6- and 7,8-benzocoumarins indicated that meta-cleavage was the major degradation mechanism of phenanthrene-1,2- and -3,4-diols. Separate cultures with 2-hydroxy-1-naphthoic acid and 1-hydroxy-2-naphthoic acid showed that the degradation rate of the former to naphthalene-1,2-diol was much faster than that of the latter. The two upper metabolic pathways of phenanthrene are converged into naphthalene-1,2-diol that is further metabolized to 2-carboxycinnamic acid and 2-hydroxybenzalpyruvic acid by ortho- and meta-cleavages, respectively. Transformation of naphthalene-1,2-diol to 2-carboxycinnamic acid by this strain represents the first observation of ortho-cleavage of two rings-PAH-diols by a Gram-negative species.

Biodegradation of polycyclic aromatic hydrocarbon by a halotolerant bacterial consortium isolated from marine environment

“…Dur in g ph en anth r ene degradation , phenanthr ene-dih ydr odiol, dih ydr oxy ph enanthrene, 1-hydroxy-2-naphthoic acid and phthalic acid were formed. Similar metabolites such as cisphenanthrene-1,2-dihydrodiol, 1-Hydroxy-2-naphthoic acid and phthalic acid formed during phenanthrene degradation were reported by Seo et al (2007). Similarly, degradation of phenanthrene by Int.…”

Waste lubricating oil removal in a batch reactor by mixed bacterial consortium: a kinetic study

“…Fatty acids are further processed by b-oxidation to generate acetyl-CoA. Based on the other two major metabolites, it could be interpreted that 3-hydroxy-2-formyl benzothiophene may be formed by partial oxidation of dibenzothiophene as reported by Khedkar and Shanker [38], whereas 1,2-dihydroxy phenanthrene may be formed by 1,2-dioxygenation pathway as described earlier in literature [39]. Further investigation on detailed biodegradation studies on individual hydrocarbons present in waste lubricating oil samples and characterization of the possible metabolites may provide real insight into the biodegradation mechanism of waste lubricating oil samples.…”

Characterization of Novel Polycyclic Aromatic Hydrocarbon Dioxygenases from the Bacterial Metagenomic DNA of a Contaminated Soil

“…Although dioxygenation of phenanthrene on the C-1 and C-2 positions has been shown to occur in Sphingomonas strain P2 (40) and in Burkholderia strain C3 (41) and gives rise to effective metabolization, most known RHDs do not generate significant amounts of 1,2-dihydrodiol from phenanthrene. In this respect, a mutant form of the naphthalene dioxygenase from Pseudomonas sp.…”