The Chemical Labeling Of Protein Dehydroalanine

The natural modifications of proteins are closely related to the functions of proteins,which regulate various physiological functions in organisms.However,in the current field of chemical biology research,the natural modifications of proteins cannot fully satisfy the researchers’ increasingly in-depth research needs for life activities.Researchers need some unnatural modified proteins that cannot be obtained through traditional gene expression technology.And the desired non-natural protein has a specific function.Therefore,researchers believe that some classic organic chemical reactions could be applied to complex organisms.Previously,it was reported that the cysteine residues of the protein were converted into dehydroalanine(Dha)by means of"chemical mutation",and then the Michael addition reaction with small molecule compounds directly site-directed modification of protein side chain residues.In this thesis,according to the theory of soft and hard acid-base,the conjugated addition reaction between sulfinic acid and dehydroalanine was studied.Firstly,more than ten kinds of small molecular compound model reactions between sulfinic acid and dehydroalanine with different structures were studied.The results show that the reaction speed of sulfurous acid with straight alkynyl structure is fast with excellent specificity.Therefore,we synthesized two kinds of labeling reagents,and modified the cysteine residues on the C2Am protein domain.It proved that the reaction can be applied to the modification of protein at side chain residues.Finally,Western blot and fluorescent labeling experiments were used to verify that our two labeling reagents can be used for protein unnatural modification efficiently."Chemical mutation" of protein cysteine to obtain dehydroalanine,and then conjugate addition reaction with sulfinic acid,can be used to simulate the oxidative modification of protein cysteine,in order to its physiological and pathological functions more in-depth research is of great significance in the field of diagnosis and treatment of related diseases and drug development.