Detection and characterization of protein nitrosothiols.

Protein S-nitrosylation is a post-translational modification of cysteine residues elicited by nitric oxide (NO). Detection and quantification of protein nitrosothiols remains a challenge because of the lability of the nitrosothiol moiety. Here, we describe approaches for labeling S-nitrosylated proteins with affinity and radioactive tags to facilitate their detection, purification, and identification.