82169-53-7

Basic information

• Product Name: Arg-Pro-Lys-Pro-Gln-Gln-Phe-Phe-Gly-Leu-Met-NH₂
• Synonyms: Arg-Pro-Lys-Pro-Gln-Gln-Phe-Phe-Gly-Leu-Met-NH₂
• CAS NO: 82169-53-7
• Molecular Weight: 1349.62
• Mol File: 82169-53-7.mol
• Article Data: 1

Chemical Properties

• CAS DataBase Reference: Arg-Pro-Lys-Pro-Gln-Gln-Phe-Phe-Gly-Leu-Met-NH₂(CAS DataBase Reference)
• NIST Chemistry Reference: Arg-Pro-Lys-Pro-Gln-Gln-Phe-Phe-Gly-Leu-Met-NH₂(82169-53-7)
• EPA Substance Registry System: Arg-Pro-Lys-Pro-Gln-Gln-Phe-Phe-Gly-Leu-Met-NH₂(82169-53-7)

Safety Data

• Hazardous Substances Data: 82169-53-7(Hazardous Substances Data)

Upstream product

• 33507-63-0 substance P 

Relevant articles and documents

Deamidation and transamidation of substance p by tissue transglutaminase revealed by electron-capture dissociation fourier transform mass spectrometry

Tissue transglutaminase (tTGase) catalyzes both deamidation and transamidation of peptides and proteins by using a peptidyl glutamine as primary substrate. A precise consensus sequence for the enzyme is unknown and the ratio between deamidated and transamidated (or cross-linked) reaction products is highly substrate-dependent. Due to its overlapping body distribution with tTGase and ease of manipulation with tandem mass spectrometry, we used the neuropeptide substance P as a model to investigate the associated enzymatic kinetics and reaction products. Online liquid-chromatography Fourier-transform ion-cyclotron-resonance mass spectrometry (FT-ICR MS) combined with electron-capture dissociation (ECD) was employed to study the tTGase-induced modifications of substance P. A particular strength of ECD for peptide-enzyme reaction product monitoring is its ability to distinguish isomeric amino acids, for example, Glu and iso-Glu, by signature product ions. Our studies show that the primary reaction observed is deamidation, with the two consecutive glutamine residues converted sequentially into glutamate: first Gln5, and subsequently Gln6. We then applied ECD FT-ICR MS to identify the transamidation site on an enzymatically cross-linked peptide, which turned out to correspond to Gln5. Three populations of substance-P dimers were detected that differed by the number of deamidated Gln residues. The higher reactivity of Gln5 over Gln6 was further confirmed by cross-linking SP with monodansylcadaverine (MDC). Overall, our approach described herein is of a general importance for mapping both enzymatically induced post-translational protein modifications and cross-linking. Finally, in vitro Ca-signaling assays revealed that the main tTGase reaction product, the singly deamidated SP (RPKPEQFFGLM-NH2), has increased agonist potency towards its natural receptor, thus confirming the biologically relevant role of deamidation.