PubMed Health⌕ Search

Biomedical subjects

D M Dietrich

Publications and source records attributed to D M Dietrich.

4 recordsLinked to original sources

Quantitation of fungal mRNAs in complex substrates by reverse transcription PCR and its application to Phanerochaete chrysosporium-colonized soil.

Thorough analysis of fungi in complex substrates has been hampered by inadequate experimental tools for assessing physiological activity and estimating biomass. We report a method for the quantitative assessment of specific fungal mRNAs in soil. The method was applied to complex gene families of Phanerochaete chrysosporium, a white-rot fungus widely used in studies of organopollutant degradation. Among the genes implicated in pollutant degradation, two closely related lignin peroxidase transcripts were detected in soil. The pattern of lignin peroxidase gene expression was unexpected; certain transcripts abundant in defined cultures were not detected in soil cultures. Transcripts encoding cellobiohydrolases and beta-tubulin were also detected. The method will aid in defining the roles of specific genes in complex biological processes such as organopollutant degradation, developing strategies for strain improvement, and identifying specific fungi in environmental samples.

Base Sequence↗

Selective Medium for Isolating Phanerochaete chrysosporium from Soil.

A selective medium was developed that is capable of isolating Phanerochaete chrysosporium from soil. This medium contains 15 ppm of benomyl (15 mug g) and 550 ppm of streptomycin sulfate in 2% malt agar and is held at 39 degrees C after inoculation. P. chrysosporium was isolated from three nonsterile forest soils to which the fungus had been added. These soils contained large microbial populations.

Journal Article↗

In Situ Depletion of Pentachlorophenol from Contaminated Soil by Phanerochaete spp.

The ability of two white rot fungi to deplete pentachlorophenol (PCP) from soil, which was contaminated with a commercial wood preservative, was examined in a field study. Inoculation of soil containing 250 to 400 mug of PCP g with either Phanerochaete chrysosporium or P. sordida resulted in an overall decrease of 88 to 91% of PCP in the soil in 6.5 weeks. This decrease was achieved under suboptimal temperatures for the growth and activity of these fungi, and without the addition of inorganic nutrients. Since the soil had a very low organic matter content, peat was included as a source of organic carbon for fungal growth and activity. A small percentage (8 to 13%) of the decrease in the amount of PCP was a result of fungal methylation to pentachloroanisole. Gas chromatographic analysis of sample extracts did not reveal the presence of extractable transformation products other than pentachloroanisole. Thus, when losses of PCP via mineralization and volatilization were negligible, as they were in laboratory-scale studies (R. T. Lamar, J. A. Glaser, and T. K. Kirk, Soil Biol. Biochem. 22:433-440, 1990), most of the PCP was converted to nonextractable soil-bound products. The nature, stability, and toxicity of soil-bound transformation products, under a variety of conditions, must be elucidated before use of these fungi in soil remediation efforts can be considered a viable treatment method.

Journal Article↗