A Metabolic Activation-Based Chemoproteomic Platform to Profile Adducted Proteins Derived from Furan-Containing Compounds

Human exposure to widespread furan-containing compounds (FCCs) has drawn much attention due to the high riskof their toxicities. Identifying adducted proteins resulting from themetabolic activation of FCCsisthecoretolearningthemechanism of FCCs'toxic action. We succeeded in establishinga metabolic activation-based chemoproteomic platform to mapFCC-derived protein adducts in cultured primary hepatocytestreated with FCCs and to pinpoint the modification sites, usingclick chemistry but without alkynylation or azidation of FCCs tobe investigated. The proposed platform was systematically verifiedby biomimetic synthesis, liver microsomal incubation, and primaryhepatocyte culture. A mixture of furan, 2-methylfuran, and 2,5-dimethylfuran as model was tested by use of the establishedplatform. A total of hepatic 171 lysine-based adducted proteins and 145 cysteine-based adducted proteins by the reactive metabolitesof the three FCCs were enriched and identified (Byonic score >= 100). The target proteins were found to mainly participate in ATPsynthesis. The technique was also successfully applied to furan-containing natural products. The established platform made itpossible to profile covalently adducted proteins, because of potential exposure to a vast inventory of over two million of FCCs documented.