Detection of S-nitrosylated protein by surface plasmon resonance

S-Nitrosylation has recently emerged as an important posttranslational modification of proteins and is becoming an intensive field of research in plants. Protein S-nitrosation, a reversible post-translation modification of cysteine, affects many cell signaling pathways and plays critical roles in redox-sensitive cell signaling. Changes in protein function effectively transmit biological signals and thus provide a framework for elucidating signaling networks. This paper presented a new, universal immunosensor for detection of S-nitrosylated proteins. Electrochemical impedance spectroscopy (EIS) and atomic force microscope (AFM) were used to estimate the formation of self-assembled film. This method was based on the specific binding characteristics of biotin–streptavidin, using Biotin-HPDP labeled protein sulfhydryl group as the substrate to detect proteins. The sensor was used to detect bovine serum albumin (BSA), nitrosylated BSA and denitrosylated BSA. The results showed that 90.61% of nitrosylated BSA were reduced, verifying that protein S-nitrosylation is a reversible and effective post-translation modification. This method was successfully applied to detect S-nitrosylated protein in Feicheng peach. The results showed good repeatability and precision. This method provided a molecular basis for further exploring the mechanism of S-nitrosylation of proteins in plants.