"Environment" research area

Understanding How Bacteria Detoxify Harmful, Aromatic Chemicals

Primary Investigator - Kathryn FixenPrincipal Investigator: Kathryn Fixen
Co-InvestigatorsJack Reddan (Undergraduate Scholar)
Award Type: Seed Grant - Undergraduate Research Scholar

Problem: Many industrial processes, like gasoline production, release toxic, aromatic (ring-structured) chemical compounds into Minnesota's groundwater. Some bacteria, like Rhodopseudomonas palustris, are capable of degrading toxic, aromatic rings through the benzoyl-CoA pathway. However, the full chemical process of detoxification is not well understood, thus limiting the ability to utilize bacteria to remediate certain chemicals from the environment.

Solution: In order to degrade aromatic compounds, bacteria must reduce, or add electrons to, benzoyl-CoA. The electrons are supplied to benzoyl-CoA by a different molecule called BadB. It is not clear where BadB and the electrons it supplies to the benzoyl-CoA pathway originate from. In other model bacteria, the enzyme 2-oxoglutarate:ferredoxin oxidoreductase, encoded by the genes korAB, is known to supply electrons to BadB molecules. To see if this also holds true for R. palustris, the Fixen Lab will genetically modify multiple R. palustris strains by deleting the korAB genes and will observe changes in the ability to degrade aromatic rings. 

Impact: The benzoyl-CoA pathway in R. palustris will be better defined through observing bacterial growth and detoxification without the korAB genes. The detoxification of aromatic chemicals already happens naturally on a global scale, but a better understanding of how the benzoyl-CoA pathway in R. palustris will allow bacteria to be used in novel remediation systems that optimize their detoxifying abilities.