protein s-nitrosylation analysis

S-Nitrosylation refers to a covalent attachment of an NO moiety to sulfhydryl residues of proteins. The sulfhydryl residues belongs to a subset of specific cysteine residues in proteins, the resulting SNO is an S-nitrosoprotein. SNOs have a short half-life in the cytoplasm because of the host of reducing enzymes, including glutathione (GSH) and thioredoxin, that denitrosylate proteins. Therefore, SNOs are often stored in membranes, vesicles, the interstitial space and lipophilic protein folds to protect them from denitrosylation. For example, caspases, which mediate apoptosis, are stored in the mitochondrial intermembrane space as SNOs.