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 risk of their toxicities.
Identifying adducted proteins resulting from the metabolic activation
of FCCs is the core to learning the mechanism of FCCs’ toxic
action. We succeeded in establishing a metabolic activation-based
chemoproteomic platform to map FCC-derived protein adducts in cultured
primary hepatocytes treated with FCCs and to pinpoint the modification
sites, using click chemistry but without alkynylation or azidation
of FCCs to be investigated. The proposed platform was systematically
verified by biomimetic synthesis, liver microsomal incubation, and
primary hepatocyte culture. A mixture of furan, 2-methylfuran, and
2,5-dimethylfuran as model was tested by use of the established platform.
A total of hepatic 171 lysine-based adducted proteins and 145 cysteine-based
adducted proteins by the reactive metabolites of the three FCCs were
enriched and identified (Byonic score ≥ 100). The target proteins
were found to mainly participate in ATP synthesis. The technique was
also successfully applied to furan-containing natural products. The
established platform made it possible to profile covalently adducted
proteins, because of potential exposure to a vast inventory of over
two million of FCCs documented.