|Chee Sanford, Joanne|
Submitted to: Microbial Ecology International Symposium
Publication Type: Abstract Only
Publication Acceptance Date: 5/2/2001
Publication Date: N/A
Citation: N/A Interpretive Summary:
Technical Abstract: Two ethanol-fed anaerobic fluidized bed reactors, one with TNT added and a control, were used to study the treatment of explosives laden wastewater. The objectives were to monitor the changes in the microbial community composition as the ethanol concentration was incrementally reduced from 532 mg/l to 33 mg/l, and to identify the microorganisms unique to the TNT-fed reactor. To accomplish this, 16S rDNA from weekly biofilm samples was amplified by PCR using a eubacterial specific primer set, with the forward primer fluorescently labeled for T-RFLP analysis. Several terminal fragments (Hha1, Rsa1, and Msp1 digests) were identified as unique to the TNT-fed system. Using the RDP's TAP T-RFLP program, one of the fragment patterns for the three digests was classified as from a Geobacter sp. As the carbon loading decreased the Geobacter associated fragments disappeared without impacting the TNT-degradation activity in the reactor. At the same time new TNT-reactor specific terminal fragments appeared as the ethanol concentration was reduced. Terminal fragments larger than 250 bases were cloned and sequenced to identify the bacteria. Results showed the presence of the Geobacter sp. and several unidentified bacteria as being potentially responsible for TNT degradation.