Molecular Biological Tools (MBTs)
What are Molecular Biological Tools (MBTs)?
Molecular Biological Tools (MBTs) are advanced DNA- and RNA-based analytical techniques used to characterize the microorganisms responsible for contaminant biodegradation in soil and groundwater. Unlike conventional groundwater chemistry, which provides indirect evidence of biodegradation, MBTs identify the microorganisms present and quantify the functional genes responsible for specific biodegradation pathways.
By evaluating microbial populations and their metabolic potential, MBTs help environmental professionals determine whether intrinsic biodegradation is occurring, identify factors limiting biological activity, and optimize remediation strategies. When combined with groundwater chemistry and Compound-Specific Isotope Analysis (CSIA), MBTs provide multiple lines of evidence to support remedial design, performance monitoring, and regulatory site closure.
Why Use Molecular Biological Tools?
MBTs provide valuable information throughout the life cycle of a remediation project by helping answer questions such as:
- Are the microorganisms capable of degrading the contaminants present?
- Which biodegradation pathways are active at the site?
- Are microbial populations responding to remedial amendments?
- Are environmental conditions favorable for continued biodegradation?
- Is additional biostimulation or bioaugmentation warranted?
- Is there sufficient evidence to demonstrate remediation progress and support site closure?
Common Applications
MBTs are routinely used to evaluate microbial activity associated with:
- Petroleum hydrocarbon biodegradation
- BTEX degradation
- Chlorinated solvent reductive dechlorination
- Chlorinated ethane degradation
- Aerobic biodegradation
- Anaerobic biodegradation
- Sulfate reduction
- Iron reduction
- Methanogenesis
- Perchlorate reductioesis
MBT Application Guides
Different contaminants are degraded through different biological pathways and require evaluation of different microbial populations and functional genes. Select an application below to learn about the microorganisms, biomarkers, and functional genes commonly evaluated for each remediation process.
Anaerobic Hydrocarbon Biodegradation
Evaluate microorganisms and functional genes associated with the anaerobic biodegradation of petroleum hydrocarbons, including BTEX compounds.
Common Biomarkers
- Benzylsuccinate Synthase (bssA)
- Anaerobic Benzene Carboxylase (abcA)
- Benzoyl-CoA Reductase (BCR)
- Geobacter spp.
- Sulfate Reducing Bacteria
- Total Bacteria
Chlorinated Ethene Reductive Dechlorination
Assess microorganisms and reductive dehalogenase genes responsible for the complete dechlorination of PCE, TCE, cis-DCE, and vinyl chloride.
Common Biomarkers
- Dehalococcoides spp.
- Reductive Dehalogenase Genes
- vcrA
- bvcA
- tceA
- pceA
- Dehalobacter
- Geobacter
- Desulfitobacterium
Chlorinated Ethane Reductive Dechlorination
Evaluate microbial populations associated with the biodegradation of chlorinated ethanes, including 1,1,1-TCA and related compounds.
Common Biomarkers
- Dehalobacter spp.
- dcaA (1,2-DCA Reductase)
- dcrA (1,1-DCA Reductase)
- cfrA (Chloroform / 1,1,1-TCA Reductase)
