Spectroscopic and molecular modeling approaches to investigate the interaction of bisphenol A, bisphenol F and their diglycidyl ethers with PPARα

A fluorescence polarization (FP) assay for the simultaneous determination of bisphenol A (BPA), bisphenol F (BPF), bisphenol A diglycidyl ether (BADGE) and bisphenol F diglycidyl ether (BFDGE) was developed. The method was based on the competition between bisphenols (BPs) and fluorescein-labeled dexamethasone derivative (Dex-fl) for mouse peroxisome proliferator-activated receptor a ligand binding domain (mPPAR alpha-LBD). A recombinant soluble protein derivative mPPAR alpha-LBD* was prepared, then in vitro binding of 4 BPs to mPPAR alpha-LBD* was investigated. Fluorescence polarization assay showed that these compounds exhibited different binding potencies with mPPAR alpha-LBD*. Additionally, molecular dynamics simulations were performed to further understand the mechanism of BPs binding affinity for mPPAR alpha-LBD*. Docking results elucidated that the driving forces for the binding of BPs to mPPARa-LBD* were predominantly dependent on hydrophobic and hydrogen-bonding interactions. Comparison of the calculated binding energies vs. experimental binding affinities yielded a good correlation (R-2 = 0.7258). The proposed method has potential for multi-residue detection of BPA, BPF, BADGE, and BFDGE. (C) 2017 Elsevier Ltd. All rights reserved.