Stability of U(VI) and Tc(VII) Reducing Microbial Communities to Environmental Perturbation: Development and Testing of a Thermodynamic Network Model
Previously published research from in situ field experiments at the NABIR Field Research Center have shown that cooperative metabolism of denitrifiers and Fe(III)/sulfate reducers is essential for creating subsurface conditions favorable for U(VI) and Tc(VII) bioreduction (Istok et al., 2004). The overall goal of this project is to develop and test a thermodynamic network model for predicting the effects of substrate additions and environmental perturbations on the composition and functional stability of subsurface microbial communities. The overall scientific hypothesis is that a thermodynamic analysis of the energy-yielding reactions performed by broadly defined groups of microorganisms can be used to make quantitative and testable predictions of the change in microbial community composition that will occur when a substrate is added to the subsurface or when environmental conditions change. An interactive computer program was developed to calculate the overall growth equation and free energy yield for microorganisms that grow by coupling selected combinations of electron acceptor and electron donor half-reactions. Each group performs a specific function (e.g. oxidation of acetate coupled to reduction of nitrate); collectively the groups provide a theoretical description of the entire natural microbial community. The microbial growth data are combined with an existing thermodynamic data base for associated geochemical reactions and used to simulate the coupled microbial-geochemical response of a complex natural system to substrate addition or any other environmental perturbations.
- Research Organization:
- Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Oregon State University, Corvallis, OR
- Sponsoring Organization:
- USDOE Office of Science (SC)
- OSTI ID:
- 893451
- Report Number(s):
- NABIR-1025387-2005; R&D Project: NABIR 1025387; TRN: US0606019
- Country of Publication:
- United States
- Language:
- English
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Final Report: Stability of U (VII) and Tc (VII) Reducing Microbial Communities To Environmental Perturbation
Thermodynamic network model for predicting effects of substrate addition and other perturbations on subsurface microbial communities
Related Subjects
54 ENVIRONMENTAL SCIENCES
59 BASIC BIOLOGICAL SCIENCES
ACETATES
BINDING ENERGY
COMMUNITIES
COMPUTER CODES
ELECTRONS
FREE ENERGY
FUNCTIONALS
HYPOTHESIS
METABOLISM
MICROORGANISMS
OXIDATION
STABILITY
SUBSTRATES
TESTING
THERMODYNAMICS
VALENCE