Genetically encoded cleavable protein photo-cross-linker.

We have developed a genetically encoded, selenium-based cleavable photo-cross-linker that allows for the separation of bait and prey proteins after protein photo-cross-linking. We have further demonstrated the efficient capture of the in situ generated selenenic acid on the cleaved prey proteins. Our strategy involves tagging the selenenic acid with an alkyne-containing dimethoxyaniline molecule and subsequently labeling with an azide-bearing fluorophore or biotin probe. This cleavage-and-capture after protein photo-cross-linking strategy allows for the efficient capture of prey proteins that are readily accessible by two-dimensional gel-based proteomics and mass spectrometry analysis.