Effects of Microbial Trophic Interactions on the Fate and Mobility of Soil Contaminants

摘要

This project will be initiated by the establishment of a culture collection isolated from contaminated drag strip soil (DSS) and clean Hudson River Sediment (HRS). Careful isolation, characterization, and long term maintenance of these bacteria and protists is critical for the success of the project. Bacteria will be characterized by sole carbon source utilization as well as standard morphological and chemical characteristics. Clonal cultures of protists will be identified by staining of morphological features for light microscopy, and characterized for their feeding and growth on the bacterial isolates obtained. Stable consortia of bacteria and protists in biphenyl cultures will be established and characterized. Retrieval of frozen consortia of bacteria and protists will be assessed. In addition, protists will be characterized for their sensitivity to biphenyl and Aroclors(R), and assayed for acquired resistance. Studies of sorption and transfer for Aroclors(R), in bacteria and protist cells will be conducted. This very basic microbial ecology work is time consuming, but is essential to lay the ground work for future experiments. Analysis of the role of protists in situ biodegradation will begin with inhibition and/or stimulation of native bacteria and protist populations. Experiments to determent the fate of Alcaligenes eutrophus H850 in soil samples with and without protists will also begin. The effects of nutrient limited growth and predation pressure as pre-adaptations to inoculation will also be determined.