HR: 17:15h
AN: B14A-06 [Abstracts]
TI: Targeted Proteomics Approaches To Monitor Microbial Activity In Basalt Aquifer
AU: * Paszczynski, A J
EM: andrzej@uidaho.edu
AF: University of Idaho
Environmental Biotechnology Institute, Food Research Center Room 103, Moscow, ID 83844-1052, United States
AU: Paidisetti, R
EM: paid8920@uidaho.edu
AF: University of Idaho
Environmental Biotechnology Institute, Food Research Center Room 103, Moscow, ID 83844-1052, United States
AB:
Microorganisms play a major role in biogeochemical cycles of the Earth. Information regarding microbial
community composition can be very useful for environmental monitoring since the short generation times of
microorganisms allows them to respond rapidly to changing environmental conditions. Microbial mediated
attenuation of toxic chemicals offers great potential for the restoration of contaminated environments in an
ecologically acceptable manner. Current knowledge regarding the structure and functional activities of microbial
communities is limited, but more information is being acquired every day through many genomic- and proteomic-
based methods. As of today, only a small fraction of the Earth's microorganisms has been cultured, and so most
of the information regarding the biodegradation and therapeutic potentials of these uncultured microorganisms
remains unknown. Sequence analysis of DNA and/or RNA has been used for identifying specific
microorganisms, to study the community composition, and to monitor gene expression providing limited
information about metabolic state of given microbial system. Proteomic studies can reveal information regarding
the real-time metabolic state of the microbial communities thereby aiding in understanding their interaction with
the environment.
In research described here the involvement of microbial communities in the degradation of anthropogenic
contaminants such as trichloroethylene (TCE) was studied using mass spectrometry-based proteomics. The co-
metabolic degradation of TCE in the groundwater of the Snake River Plain Aquifer at the Test Area North (TAN)
site of Idaho National Laboratory (INL) was monitored by the characterization of peptide sequences of enzymes
such as methane monooxygenases (MMOs). MMOs, expressed by methanotrophic bacteria are involved in the
oxidation of methane and non-specific co-metabolic oxidation of TCE. We developed a time- course cell lysis
method to release proteins from complex microbial communities to allow for better identification of specific
proteins. This method not only identified the proteins of interest but also increased the peptide coverage and
increased the number of proteins identified. We were able to identify methane monooxygenase proteins within
TAN site microbial communities supporting the occurrence of co-metabolic oxidation of TCE in this aquifer. We
correlated methane monooxygenase presence with the number of methanotrophs in the samples obtained
through quantitative PCR and quantitative proteomic methods. Utilization of this extraction method in combination
with UPLC/MS/MS resulted in successful extraction, identification, and quantification of MMO-derived biomarker
peptides from both pure cultures and environmental samples.
Along with MMO proteins, we identified proteins from non-methanotrophic organisms that may play major roles in
macronutrients turnover and the attenuation of TCE in the TAN aquifer.
UR: http://www.ebi.uidaho.edu/default.aspx?pid=99130
DE: 0400 BIOGEOSCIENCES
DE: 0418 Bioremediation
DE: 0428 Carbon cycling (4806)
DE: 0471 Oxidation/reduction reactions (4851)
SC: Biogeosciences [B]
MN: 2007 Fall Meeting