The study of phosphorylated proteins and peptides can help people to explain the mechanism of the above processes and further understand the essence of life activities. In recent years, with the continuous development of proteome technology, protein phosphorylation has attracted more and more attention. Many natural toxins and causative agents exert their effects by altering the phosphorylation of intracellular proteins.
Phosphorylation polypeptide mainly refers to the side chain hydroxyl groups of Ser, Tyr and Thr residues in the peptide chain are modified into acid phosphate peptides. Up to now, there are two main methods of phosphorylation modification of peptides: post-phosphorylation method and single method.
When modified by single method, it is difficult to condensed with peptide chain due to the steric hindrance of large groups modified by side chain, and the subsequent introduction of amino acid will be difficult, especially when there are multiple phosphorylation sites, the synthesis will become extremely difficult, and the final product is complex, difficult to separate and the yield is very low. Therefore, when multiple sites in the peptide chain are phosphorylated, the post-phosphorylation method can be considered. The main synthesis process is to selectively remove the side chain protective group of the amino acid to be marked after the peptide synthesis is completed. For Tyr,Thr, the side chain unprotected amino acid can be directly used to react. The side chain protective group can be quantitatively removed under the condition of 1% TFA/DCM. After phosphorylation, dibenzylidene phosphoamide and tetrazolium can be used to form phosphoametrazole active intermediate, which can be connected to hydroxyl group, and then oxidized to form phosphate group under peracetic acid condition to complete the reaction.
· We provide phosphorylation modification services for pSer, pTyr, pThr and D-pSer, D-pTyr, D-pThr.
· Phosphorylation of 2 sites, 3 sites, 4 sites and 5 sites can be carried out simultaneously.
Phosphorylated polypeptide synthesis cases (Thr (HPO3), Tyr (HPO3), Ser (HPO3), etc.)
- There were 4 phosphorylation sites in the sequence (xxxpSpTxxxpSxxxpTx), the purity was 95%, and the completion period was 3 weeks.
HPLC analysis:
MS Atlas:
