Fluorescence probe techniques to study the interaction between hydroxylated polybrominated diphenyl ethers (OH-PBDEs) and protein disulfide isomerase (PDI)

A selective and sensitive method to study the interaction between hydroxylated polybrominated diphenyl ethers (OH-PBDEs) and protein disulfide isomerase (PDI) was established in this assay. In this report, 3,3',5-triiodo-thyronine (T3) was conjugated with fluorescein (FITC) as a fluorescence probe (F-T3) to study the competitive binding interaction of OH-PBDEs to PDI, which was observed to exhibit T3 binding activity. The findings suggest that some OH-PBDEs have the potential of binding to PDI, and they share the same binding site as T3 to PDI; moreover, OH-PBDEs were able to act as a competitive inhibitor in PDI binding to T3.