双酚A(BPA)是一种内分泌干扰化合物,BPA与载体蛋白的结合机制受到广泛关注。卤素取代可以显着影响BPA的性质,对人体健康产生各种影响。这里,我们选择四溴双酚A(TBBPA)和四氯双酚A(TCBPA)来研究不同卤素取代的BPAs与人血清白蛋白(HSA)之间的相互作用。TBBPA/TCBPA自发占据位点I并与HSA形成稳定的二元复合物。与TCBPA相比,TBBPA对HSA具有较高的结合亲和力。与TCBPA相比,不同卤素取代基对BPA带负电荷的表面积的影响是TBBPA与HSA的结合亲和力较高的重要原因。氢键和范德华力在TCBPA-HSA复合物中至关重要,而TBBPA-HSA复合物形成的主要驱动因素是疏水相互作用。此外,TBBPA/TCBPA的存在改变了HSA的二级结构。发现氨基酸残基如Lys199、Lys195、Phe211、Arg218、His242、Leu481和Trp214在BPA化合物和HSA之间的结合过程中起关键作用。此外,卤素取代基的存在促进了BPA化合物与HSA的结合。
Bisphenol A (BPA) is an endocrine-disrupting compound, and the binding mechanism of BPA with carrier proteins has drawn widespread attention. Halogen substitutions can significantly impact the properties of BPA, resulting in various effects for human health. Here, we selected tetrabromobisphenol A (TBBPA) and tetrachlorobisphenol A (TCBPA) to investigate the interaction between different halogen-substituted BPAs and human serum albumin (HSA). TBBPA/TCBPA spontaneously occupied site I and formed stable binary complexes with HSA. Compared to TCBPA, TBBPA has higher binding affinity to HSA. The effect of different halogen substituents on the negatively charged surface area of BPA was an important reason for the higher binding affinity of TBBPA to HSA compared to TCBPA. Hydrogen bonds and van der Waals forces were crucial in the TCBPA-HSA complex, while the main driving factor for the formation of the TBBPA-HSA complex was hydrophobic interactions. Moreover, the presence of TBBPA/TCBPA changed the secondary structure of HSA. Amino acid residues such as Lys199, Lys195, Phe211, Arg218, His242, Leu481, and Trp214 were found to play crucial roles in the binding process between BPA compounds and HSA. Furthermore, the presence of halogen substituents facilitated the binding of BPA compounds with HSA.