Sensitivity to and Degradation of Pentachlorophenol by Phanerochaete spp

Abstract

This research measured mycelial extension rates of selected strains of Phanerochaete chrysorhiza, Phanerochaete laevis, Phanerochaete sanguinea, Phanerochaetefilamentosa, Phanerochaete sordida, Inonotus circinatus, and Phanerochaete chrysosporium and the ability of these organisms to tolerate and degrade the wood preservative pentachlorophenol (PCP) in an aqueous medium and in soil. Most of the tested species had mycelial extension rates in the range of c0.5 to 1.5 cm day-', but there were large interspecific differences. A notable exception, P. sordida, grew very rapidly, with an average mycelial extension rate of 2.68 cm day-' at 28°C. Rank of species by growth rate was as follows: P. chrysosporium > P. sordida > P. laevis > P. chrysorhiza = P. sanguinea > I. circinatus = P. filamentosa. There were also significant intraspecific differences in mycelial extension rates. For example, mycelial extension rates among strains of P. sordida ranged from 1.78 to 4.81 cm day-'. Phanerochaete spp. were very sensitive to PCP. Growth of several species was prevented by the presence of 5 ppm (5 ,ug/g) PCP. However, P. chrysosporium and P. sordida grew at 25 ppm PCP, albeit at greatly decreased mycelial extension rates. In an aqueous medium, mineralization of PCP by P. sordida 13 (ca. 12% after 30 days) was significantly greater than that by all other tested P. sordida strains and P. chrysosporium. After 64 days, the level of PCP had decreased by 96 and 82% in soil inoculated with P. chrysosporium and P. sordida, respectively. Depletion of PCP by these fungi occurred in a two-stage process. The first stage was characterized by a rapid depletion of PCP that coincided with an accumulation of pentachloroanisole (PCA). At the end of the first stage, ca. 64 and 71% of the PCP was converted to PCA in P. chrysosporium and P. sordida cultures, respectively. In the second stage, levels of PCP and PCA were reduced by 9.6 and 18%, respectively, in soil inoculated with P. chrysosporium and by 3 and 23%, respectively, in soil inoculated with P. sordida. PCA was mineralized by both P. chrysosporium and P. sordida in an aqueous medium.

One-electron oxidation in the degradation of creosote polycyclic aromatic hydrocarbons by Phanerochaete chrysosporium

“…Stock cultures of P. chrysosporium Burdsall BKM-F-1767 (ATCC 24725) were obtained from the Center for Forest Mycology Research, Forest Products Laboratory, Madison, Wis. These were subcultured onto yeast extractmalt extract-peptone-glucose (YMPG) slants (18) and maintained at 4ЊC until use.…”

Microbial breakdown of halogenated aromatic pesticides and related compounds

“…Mineralization of pentachlorophenoI was, however, negligible and most of the loss was presumably due to O-methylation to pentachloroanisole [71] (see section 3.4). Some mineralization of both pentachlorophenol and pentachloroanisole in liquid cultures of P. chrysosporium and P. sordida was however observed [71].…”

“…Several species of Gram-positive and Gramnegative bacteria belonging to the genera Acinetobacter, Pseudomonas, Mycobacterium, and Rhodococcus have been shown to O-methylate chlorinated phenols and chlorophenol derivatives [104,[106][107][108][109][110][111][112]. O-Methylation of chlorophenols to the corresponding chloroanisoles has also frequently been observed with different species of fungi [71,[113][114][115][116][117]. The ability to O-methylate chlorophenols is thus widespread in nature.…”

Investigations of Enzymatic Alterations of 2,4-Dichlorophenol Using 13c-Nuclear Magnetic Resonance in Combination With Site-Specific 13c-Labeling: Understanding the Environmental Fate of This Pollutant

“…Therefore, to truly understand the biodegradation of pollutants, it is necessary to have knowledge regarding their environmental fate, the mechanistic pathways, the formation of by-products, and the possible covalent and noncovalent interactions of the pollutant molecules with naturally present organic matter. Clearly, bioremediation assessment requires much more than merely monitoring the disappearance and mineralization rate of the pollutant compounds, which are typically the only measurements acquired [6][7][8][9][10].…”

“…Using this approach, we took this technique one step further and examined the degradation of 2,4-DCP by the white-rot fungi Phanerochaete chrysosporium. This species has been shown to mineralize polychlorinated phenols present in a pure culture [10,17], in contaminated wood samples [18], and in contaminated soil samples [7,8,19,20]. Phanerochaete chrysosporium has also been shown to degrade and mineralize a wide array of other aromatic, recalcitrant pollutant compounds [21][22][23], such as polycyclic aromatic hydrocarbons; chlorinated aromatic hydrocarbons; pesticides such as DDT, chlordane, and lindane; and munitions such as 2,4,6-trinitrotoluene.…”