Projects & Research
The Applied Environmental Microbiology (AEM)
Core is the source of environmental data and samples that determine
the stressors that will be studied, provides the environments for
growing the organisms to be tested, simulates stressed environments,
and verifies the conceptual models to determine how these stress
regulatory pathways control the biogeochemistry of contaminated sites.
The specific goals of the AEM Core are to:
- Survey and map DOE sites contaminated by metals
and radionuclides using chemical and molecular/ microbiological
parameters to determine major microbial populations and potential
stressors for Desulfovibrio vulgaris, Geobacter metallireducens,
and Shewanella oneidensis MR1.
- Determine the rank priority of these stressors
in terms of their ability to affect metal/radionuclide bioreduction
by either direct or indirect processes, and to establish the
normal active range of the stressor in metal/radionuclide contaminated
- Determine the incidence and activity of the
three target bacteria, and closely related relatives, in the
test metal/radionuclide contaminated environments and collect
isolates for analysis by the Functional Genomics Core for comparison
using 16S RNA profiling.
- Create defensible environmental simulators
that can replicate key features of field site chemical and biological
structure to mimic stress conditions for single populations and
later for microbial communities (chemostats to soil columns from
10 µm to 1 m size systems).
- Provide large quantities of cells in various
stress states for the Functional Genomics Core’s physiological
monitoring facility, molecular interaction studies, and combinatorial
- Provide environmental simulators for testing
stressor effects on mutants, large insert clones, expression
analysis, etc., for elucidating critical parts of the stress
- Develop testable conceptual models of stress
regulatory pathways based on results of the Computational Core
that could predict natural attenuation and suggest biostimulatory
strategies for immobilization of metals and radionuclides at
DOE contaminated sites.
- Test conceptual models of stress regulatory
pathways and effects on contaminate site biogeochemistry using
competent soil columns with different levels of complexity over
the active range of the stressors.
- Validate conceptual models using field tests
at contaminated sites that utilize specific functional gene arrays
developed from the stress regulatory pathways.
- Alter field conditions or test along gradients
to verify stress regulatory model efficiency for predicting natural
attenuation or suggesting biostimulatory strategies for immobilization
of metals and radionuclides.