ERRγ tethers strongly bisphenol A and 4-α-cumylphenol in an induced-fit manner

A receptor-binding assay and X-ray crystal structure analysis demonstrated that the endocrine disruptor bisphenol A (BPA) strongly binds to human estrogen-related receptor γ (ERRγ). BPA is well anchored to the ligand-binding pocket, forming hydrogen bonds with its two phenol-hydroxyl groups. In this study, we found that 4-α-cumylphenol lacking one of its phenol-hydroxyl groups also binds to ERRγ very strongly. The 2.0 Å crystal structure of the 4-α-cumylphenol/ERRγ complex clearly revealed that ERRγ’s Leu345-β-isopropyl plays a role in the tight binding of 4-α-cumylphenol and BPA, rotating in a back-and-forth induced-fit manner.