Phosphorylated and Sulfated Peptides

Phosphorylation:

Phosphorylation isthe main form of reversible covalent modification of proteins for their regulation. This is catalyzed by a large family of enzymes called protein kinases. The dephosphorylation of phosphoproteins is carried out by another group of enzymes called protein phosphatases. The study of these enzymes and their phosphoprotein targets (also known as substrates) is having an enormous impact on our understanding of how cells are controlled and human health care delivery.

Phosphopeptides are essential tools for the study of phosphorylation process, serving as model substrates for phosphatases, as antigens for the production of antibodies against phosphorylated proteins, and as reference compounds for determining their physical parameters. The development of methods for the production of phosphopeptides has consequently attracted considerable interest over the last few years, and these endeavours have yielded reliable procedures which have now made their synthesis routine.

However, during the synthesis of phosphopeptides, the presence of phosphoamino acids cannot only make the coupling reaction sluggish but also induce the ease of assembling peptide chains, leading to a significant decrease of coupling efficiency. Consequently, the purity of crude product and the purification yield will be dramatically lowered, and in some serious cases complete reaction failure will result. After optimization of synthesis conditions when incorporating phosphoamino acids as well as consecutive amino acids, we successfully prepared peptides containing as many as six phosphorylation sites with the building block approach.

※ We offer phosphorylation on pSer, pTyr, pThr or D-pSer, D-pTyr, D-pThr.

※ Phosphorylation is available in two sites, three sites, four sites and five sites

Tyr(SO3H):

Sulfation of tyrosine residues is an important post-translational modification that occurs on manysecretory as well as transmembrane proteins. It has been suggested that up to 1% of all tyrosine residues of the overall protein content in an organism are sulfated which makes this modification essential for numerous biological processes. However, one of the factors hindering the study of the significance of sulfotyrosine (sTyr) within a protein is the absence of a general method that enables the synthesis of sTyr peptides in satisfactory yields and purity.
Though employing the proper building blocks and optimizing the final cleavage protocol, Scilight has successfully synthesized a lot of Tyr(SO3H) bearing peptides for research institutes and colleges all over the world.