| Abstract
| - The metabolites of polychlorinated biphenyls (PCBs),such as hydroxylated PCBs (OH-PCBs), have been identified as environmental contaminants. Various studies haveshown that some OH-PCBs can potentially contribute tohealth problems. Detection of these compounds in environmental and biological samples could provide usefulinformation about their levels and lead to a better understanding of their apparent toxicity. To that end, we havedeveloped a whole-cell sensing system for the detectionof OH-PCBs by taking advantage of the recognition of agroup of related compounds, i.e., hydroxylated biphenyls,by the product of the hbpR gene in the hbp operon fromPseudomonas azelaica strain HBP1. By fusing theluxAB genes, encoding the reporter protein bacterialluciferase, to the hbp regulator−promoter sequence, awhole-cell sensing system was developed. Here, we describe the optimization and application of this whole-cellsensing system for the detection of a model compound,2-hydroxy-3‘,4‘-dichlorobiphenyl. A detection limit of 1× 10-8 M was achieved using this system. The detectionof a broad range of individual OH-PCBs as well as an OH-PCB mixture was investigated. The system can detect OH-PCBs in whole serum samples in a trace amount, whichis comparable to the detection of these analytes inmedium alone. We envision that the method developedcan potentially be employed as a rapid and sensitive wayto monitor OH-PCBs for toxicological study in the laboratory, as well as a useful tool to evaluate the presence ofbioavailable OH-PCBs in natural environments.
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