Pdx1–SBM2 peptide

Pdx1–SBM2 peptide

• Handling and Storage of Synthetic Peptides
• Material Safety Data Sheets (MSDS)

H-LSASPQPSSVAPRRPQEPR-OH

H-Leu-Ser-Ala-Ser-Pro-Gln-Pro-Ser-Ser-Val-Ala-Pro-Arg-Arg-Pro-Gln-Glu-Pro-Arg-OH

19

95.25%

C₈₇H₁₄₆N₃₀O₂₈

2060.26

Synthetic

Powder

Pdx1-SBM2 is a peptide that contains a specific binding motif for the protein SPOP. It is a second SPOP-binding motif within Pdx1-C, which differs from all other structurally characterized substrate SB motifs as the serine in position 3 of the consensus sequence is not conserved. In Pdx1-SBM2, a proline resides in position 3, but the peptide is stabilized by H-bonding by the serine residues in positions 4 and 5. The distinctive internal Pro is flanked by four of the five backbone contacts, three of which are unique to SBM2. The Pro in this position could help preorganize the Pdx1 backbone to favor these interactions upon binding.

Normally, this peptide will be delivered in lyophilized form and should be stored in a freezer at or below -20 °C. For more details, please refer to the manual:Handling and Storage of Synthetic Peptides

• Usher ET, Sabri N, Rohac R, Boal AK, Mittag T, Showalter SA. Intrinsically disordered substrates dictate SPOP subnuclear localization and ubiquitination activity. J Biol Chem. 2021 Jan-Jun;296:100693. doi: 10.1016/j.jbc.2021.100693. Epub 2021 Apr 22. PMID: 33894201; PMCID: PMC8138767.

Trifluoroacetic acid (TFA) has a significant impact on peptides due to its role in the peptide synthesis process.

TFA is essential for the protonation of peptides that lack basic amino acids such as Arginine (Arg), Histidine (His), and Lysine (Lys), or ones that have blocked N-termini. As a result, peptides often contain TFA salts in the final product.

TFA residues, when present in custom peptides, can cause unpredictable fluctuations in experimental data. At a nanomolar (nM) level, TFA can influence cell experiments, hindering cell growth at low concentrations (as low as 10 nM) and promoting it at higher doses (0.5–7.0 mM). It can also serve as an allosteric regulator on the GlyR of glycine receptors, thereby increasing receptor activity at lower glycine concentrations.

In an in vivo setting, TFA can trifluoroacetylate amino groups in proteins and phospholipids, inducing potentially unwanted antibody responses. Moreover, TFA can impact structure studies as it affects spectrum absorption.