FcIII peptide

FcIII peptide

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

H-DCAWHLGELVWCT-OH

H-Asp-Cys-Ala-Trp-His-Leu-Gly-Glu-Leu-Val-Trp-Cys-Thr-OH

13

95.57%

C₆₉H₉₇N₁₇O₁₉S₂

1532.73

Synthetic

Powder

The FcIII peptide is a 13 amino acid peptide (DCAWHLGELVWCT) that has been shown to bind competitively to hinge region on the Fc fragment of IgG with high affinity. It was initially identified through a bacteriophage display screen. A modified version of the FcIII peptide, called Bio-Ox, was developed to increase solubility and enable competitive elution of protein complexes in their native state. Further modifications were made to improve solubility, resulting in a new reagent called PEGylOx. PEGylOx is an FcIII peptide that is N-terminally PEGylated with a four-unit polymer and cyclized by oxidation of the cysteines to cystine. PEGylOx has been used for the rapid, native elution of protein complexes containing a Protein-A-tagged component from yeast and bacteria.

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

• LaCava J, Chandramouli N, Jiang H, Rout MP. Improved native isolation of endogenous Protein A-tagged protein complexes. Biotechniques. 2013 Apr;54(4):213-6. doi: 10.2144/000114012. PMID: 23581468; PMCID: PMC3667664.

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.