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Updated: Aug 10, 2026

Biochemical and Structural Characterization of the Carbohydrate Transport Substrate-binding-protein SP0092
Published on: October 2, 2017
A metabolite of acetaminophen covalently binds to the 56 kDa selenium binding protein
N R Pumford1, B M Martin, J A Hinson
1Department of Pharmacology and Toxicology, University of Arkansas for Medical Sciences, Little Rock 72206.
Abstract:
Acetaminophen is metabolized by cytochrome P450 to a reactive metabolite that covalently binds to proteins and this binding correlates with the hepatotoxicity. The major protein adduct was previously reported to be a 55 kDa protein that was detected on Western blots using antisera specific for 3-(cystein-S-yl)acetaminophen. In this study, the 55 kDa protein was isolated using a combination of ion exchange fast flow chromatography, hydroxyapatite HPLC and anion exchange HPLC. Amino acid sequences of 8 internal peptides from a trypsin digestion of the 55 kDa protein were found to have 97% homology with the deduced amino acid sequence from a cDNA that corresponds to a 56 kDa selenium binding protein. This is the first report of a specific protein to which a metabolite of acetaminophen covalently binds.
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