L17E peptide (TFA removed)

L17E peptide (TFA removed)

• COA/MS/HPLC Report
• Handling and Storage of Synthetic Peptides
• Material Safety Data Sheets (MSDS)

Batch to batch variation of the purity

H-IWLTALKFLGKHAAKHEAKQQLSKL-NH2

H-Ile-Trp-Leu-Thr-Ala-Leu-Lys-Phe-Leu-Gly-Lys-His-Ala-Ala-Lys-His-Glu-Ala-Lys-Gln-Gln-Leu-Ser-Lys-Leu-NH2

25

95.46%

C₁₃₄H₂₂₀N₃₈O₃₁

2859.4

Synthetic

Powder

L17E is an endosomolytic peptide derived from the cationic and membrane-lytic spider venom peptide M-lycotoxin and contains a substitution of leucine by glutamic acid at position 17. L17E is able to promote the endocytic uptake and cytosolic delivery of exosome-encapsulated proteins. A major obstacles to intracellular targeting by antibodies is the limited release of the antibodies into the cytosol, once inside endosomes. L17E can achieve an enhanced cellular uptake via the induction of micropinocytosis. Once inside the endosome, positively charged L17E is able to preferentially disrupt negatively charged endosomal membranes to enable a marked cytosolic liberation of antibodies (immunoglobulins G (IgGs)) from endosomes. L17E had little pH dependence and no enhanced helical structure is needed for L17E-mediated membrane lysis.

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

• Akishiba et al., (2017). Cytosolic antibody delivery by lipid-sensitive endosomolytic peptide. Nature Chemistry. 9. 751.

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.