Modeling Selenoprotein Se-Nitrosation: Synthesis of a Se-Nitrososelenocysteine with Persistent Stability

The Se-nitrosation in selenoproteinssuch as glutathioneperoxidase and thioredoxin reductase to produce Se-nitrososelenocysteines (Sec-SeNOs) has been proposed to playcrucial roles in signaling processes mediated by reactive nitrogenspecies and nitrosative-stress responses, although chemical evidencefor the formation of Sec-SeNOs has been elusive not only inproteins but also in small-molecule systems. Herein, we report thefirst synthesis of a Sec-SeNO by employing a selenocysteinemodel system that bears a protective molecular cradle. The Sec-SeNOwas characterized using H-1 and Se-77 nuclearmagnetic resonance as well as ultraviolet/visible spectroscopy andfound to have persistent stability at room temperature in solution.The reaction processes involving the Sec-SeNO provide experimentalinformation that serves as a chemical basis for elucidating the reactionmechanisms involving the SeNO species in biological functions, aswell as in selenol-catalyzed NO generation from S-nitrosothiols.

Automated summary

This study reports the first synthesis of a Sec-SeNO using a selenocysteine model system with a protective molecular cradle. The Sec-SeNO was characterized using various techniques and found to be stable at room temperature. The findings provide a chemical basis for understanding the reaction mechanism of SeNO species in biological functions.