Hydroxylated polychlorinated biphenyl detection based on a genetically engineered bioluminescent whole-cell sensing...

Area of Science:

• Environmental Science
• Biotechnology
• Toxicology

Background:

• Polychlorinated biphenyls (PCBs) and their metabolites, hydroxylated PCBs (OH-PCBs), are persistent environmental contaminants.
• Certain OH-PCBs are associated with adverse health effects, necessitating sensitive detection methods.
• Existing detection methods may lack the sensitivity or speed required for comprehensive environmental and toxicological assessments.

Purpose of the Study:

• To develop and optimize a whole-cell sensing system for the detection of hydroxylated PCBs (OH-PCBs).
• To assess the system's sensitivity and applicability for detecting individual OH-PCBs and mixtures.
• To evaluate the potential of the biosensor for monitoring OH-PCBs in biological and environmental matrices.

Main Methods:

• Engineered a whole-cell biosensor by fusing the luxAB reporter genes to the hbp regulator-promoter sequence from Pseudomonas azelaica HBP1.
• Utilized the hbpR gene product's recognition of hydroxylated biphenyls for specific OH-PCB detection.
• Optimized the system for detecting a model compound (2-hydroxy-3',4'-dichlorobiphenyl) and tested its performance with various OH-PCBs and serum samples.

Main Results:

• Achieved a detection limit of 1 x 10(-8) M for the model OH-PCB compound.
• Demonstrated the system's capability to detect a range of individual OH-PCBs and a mixture.
• Successfully detected trace amounts of OH-PCBs in whole serum samples, comparable to detection in medium alone.

Conclusions:

• The developed whole-cell sensing system provides a rapid and sensitive method for OH-PCB detection.
• This biosensor can be valuable for toxicological studies and monitoring bioavailable OH-PCBs in natural environments.
• The system offers a promising tool for assessing the risks associated with OH-PCB contamination.