Tachyplesin-1/RP557 peptide

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

Batch to batch variation of the purity

RP557 is a designed antimicrobial peptide (dAMP) derived from tachyplesin I, a disulfide β-sheet antimicrobial peptide found in the horseshoe crab Tachypleus tridentatus. It consists of 17 amino acids with the sequence RFCWKVCYKGICFKKCK and features disulfide bridges between C3–C16 and C7–C12. RP557 exhibits broad-spectrum antifungal activity against various Candida species, including fluconazole-resistant strains such as C. albicans, C. glabrata, and C. tropicalis, with MIC values ranging from 1.9 to 15 μM (4 to 32 μg/ml). The peptide demonstrates potent fungicidal activity, as evidenced by minimal differences between its MIC and MFC values.

RP557 is particularly effective against Candida biofilms, inhibiting both biofilm formation and disrupting preformed biofilms at concentrations lower than those required for planktonic cells. Scanning electron microscopy reveals that RP557 induces significant membrane perturbation in fungal cells, leading to cell wall damage. Additionally, RP557 shows limited cytotoxicity to mammalian cells, with an LD₁₀ of 287 μg/ml (134 μM) in human keratinocytes, indicating selective antifungal action. Its mechanism involves direct membranolytic activity, likely due to electrostatic interactions with fungal membranes, and it exhibits a low propensity for inducing resistance in Candida species.

• 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) is a common counterion from the purification process using High-Performance Liquid Chromatography (HPLC). The presence of TFA can affect the peptide's net weight, appearance, and solubility.

Impact on Net Weight: The TFA salt contributes to the total mass of the product. In most cases, the peptide content constitutes >80% of the total weight, with TFA accounting for the remainder.

Solubility: TFA salts generally enhance the solubility of peptides in aqueous solutions.

In Biological Assays: For most standard in vitro assays, the residual TFA levels do not cause interference. However, for highly sensitive cellular or biochemical studies, please be aware of its presence.