Effect of Protein Glycosylation on Pollution Control of Benzo[a]pyrene and Its Metabolites

Interactions of Benzo[a]pyrene (B[a]P) and its 3 typical oxygenated metabolites (B[a]P-7,8-oxide, B[a]P-7,8-diol and (+)-B[a]P-7,8-Diol-9,10-epoxide) with HSA and glycated HSA were studied by molecular docking. The results showed that they could strongly bind to HSA and gHSA within different binding sites. The binding energy of the 4 molecules with HSA was ranked by B[a]P-7,8-oxide > B[a]P-7,8-diol > B[a]P > (+)-B[a]P-7,8-diol-9, 10-epoxide, while that of gHSA was ranked by B[a]P > B[a]P-7,8-oxide > B[a]P-7,8-diol > (+)-B[a]P-7,8-diol-9,10-epoxide. Compared with HSA, the binding energy of B[a]P and gHSA was increased, while that of the other 3 molecules with gHSA was decreased to varying degrees. They bind to HSA and gHSA mainly through hydrophobic and hydrogen bonding. This work explored the differences in the mechanism of action between the 4 pollutants and HSA or gHSA from the molecular and even atomic levels, indicating that glycation of HSA significantly affects its binding ability with pollutants. The results obtained can provide theoretical support for more accurate understanding of the transport, elimination, toxification process and pollution control of B[a]P pollutants in the human body.