Characterization of Reductive-Dechlorinating Microbial Communities Using a Combination of Fluorescent In Situ Hybridization and PCR-Based Molecular Tools

EPA Grant Number: U915559
Title: Characterization of Reductive-Dechlorinating Microbial Communities Using a Combination of Fluorescent In Situ Hybridization and PCR-Based Molecular Tools
Investigators: Richardson, Ruth E.
Institution: University of California - Berkeley
EPA Project Officer: Jones, Brandon
Project Period: December 1, 1999 through December 1, 2001
Project Amount: $73,516
RFA: STAR Graduate Fellowships (1999) RFA Text |  Recipients Lists
Research Category: Academic Fellowships , Engineering and Environmental Chemistry , Fellowship - Engineering

Objective:

The objective of this research project is to understand the microbial community structure of a mixed culture that fully dechlorinates chlorinated aliphatic hydrocarbons to ethene. Additional characterization of a partially dechlorinating culture (which produces vinyl chloride as the primary end-product) will provide evidence as to which populations are essential for the final and most important (from a public health standpoint) dechlorination step that converts vinyl chloride to ethene. By using a combination of molecular tools, it is possible to get a more complete picture of community structure than any single method would allow.

Approach:

In this study, two dechlorinating mixed cultures will be characterized and compared by a combination of 16S rDNA-based molecular methods: terminal restriction fragment length polymorphisms (T-RFLP), RFLP and sequencing of individual clones from clone libraries constructed from amplified community DNA, and fluorescent in situ hybridization (FISH). The cultures will originate from a soil sample from Alameda Naval Air Station that is contaminated with a combination of hydrocarbons and trichloroethene (TCE). One culture completely dechlorinates TCE and perchloroethene (PCE) to ethene, while the second, daughter culture dechlorinates only to vinyl chloride (VC), a known human carcinogen.

Expected Results:

This method of using a combination of molecular tools to characterize mixed cultures will make it possible to get a more complete picture of community structure than any single method would allow.

Supplemental Keywords:

reductive dechlorination, Dehalococcoides, chlorinated ethenes, TCE, FISH, T-RFLP, community structure, bioremediation., RFA, Scientific Discipline, Waste, Water, Ecosystem Protection/Environmental Exposure & Risk, Chemical Engineering, Environmental Chemistry, Remediation, Restoration, Hazardous Waste, Bioremediation, Aquatic Ecosystem Restoration, Environmental Engineering, Groundwater remediation, Hazardous, Engineering, Chemistry, & Physics, dechlorination, microbiology, monitoring, hazardous waste treatment, reductive dehalogenation, bioremediation model, microbial degradation, in situ treatment, advanced treatment technologies, in situ remediation, biodegradation, dehalogenate, TCE degradation, acuatic ecosystems, biotechnology, in-situ bioremediation, aquifer remediation design, dehalogenation, fluorescent in situ hybridization, reductive dechlorination, contaminated groundwater, groundwater contamination, bioaugmentation, contaminated aquifers, groundwater pollution, degrade trichloroethylene, groundwater, aquifer remediation