A Quantitative Chemoproteomic Platform to Monitor Selenocysteine Reactivity within a Complex Proteome (Cell Chemical Biology)

Bak et al. describe a chemoproteomic method for the global enrichment and identification of selenocysteine (Sec) residues. Low-pH iodoacetamide-alkyne labeling masks Cys reactivity, allowing for tissue-specific selenoprotein identification. This platform shows promise for interrogating the specificity of Sec inhibitors, such as auranofin.