RP557 peptide

RP557 peptide

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

H-RFCWKVCYKGICFKKCK-NH2 (disulfide bridge: C3–C16, C7–C12)

H-Arg-Phe-Cys-Trp-Lys-Val-Cys-Tyr-Lys-Gly-Ile-Cys-Phe-Lys-Lys-Cys-Lys-NH2

17

95.6%

C₉₉H₁₅₁N₂₇O₁₈S₄

2135.68

Synthetic

Powder

Candida did not develop resistance, under the specific experimental conditions used, against RP554, RP556, and RP557. RP557 exhibited broad-spectrum antifungal activity against 46 clinical isolates comprising fluconazole-sensitive and resistant strains of C. albicans, C. glabrata, C. tropicalis, and C. parapsilosis and intrinsically resistant C. krusei. RP557 is a potential therapeutic for the treatment of vulvovaginal candidiasis.

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

• Woodburn KW, Clemens LE, Jaynes J, et al. Designed Antimicrobial Peptides for Recurrent Vulvovaginal Candidiasis Treatment. Antimicrob Agents Chemother. 2019;63(11):e02690-18. Published 2019 Oct 22. doi:10.1128/AAC.02690-18

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.