VLL-28 peptide

VLL-28 peptide

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

Batch to batch variation of the purity

H-VLLVTLTRLHQRGVIYRKWRHFSGRKYR-OH

H-Val-Leu-Leu-Val-Thr-Leu-Thr-Arg-Leu-His-Gln-Arg-Gly-Val-Ile-Tyr-Arg-Lys-Trp-Arg-His-Phe-Ser-Gly-Arg-Lys-Tyr-Arg-OH

28

95.2%

C₁₆₃H₂₆₄N₅₄O₃₅

3540.17

Synthetic

Powder

The antimicrobial peptide VLL-28, isolated from an archaeal transcription factor, shows comparable antifungal activity against 10 clinical isolates of Candida spp. VLL-28 binds to the surface of planktonic cells. VLL-28 effectively reduced the viability of the cells embedded in the mature biofilms, with MBEC50 and MBEC80 of 50 μM and 100 μM, respectively, for C. albicans isolates and the reference strain. In addition, VLL-28 killed 50% of the cells in the preformed biofilm (MBEC50) of C. glabrata and C. parapsilosis isolates at a concentration of 100 μM. On the other hand, VLL-28 was less effective against the mature biofilms of C. tropicalis and C. krusei isolates. VLL-28 is a cryptic antimicrobial peptide derived from a transcriptional factor of Sulfolobus islandicus. VLL-28 displayed a reduced activity only towards C. glabrata, which showed the highest MIC and MFC values . VLL-28 also exhibited strong fungicidal activity towards the planktonic cells of C. krusei. VLL-28 interacts primarily with the fungal surfaces. VLL-28 behaves as a typical CAMP by damaging the cell membrane and/or the cell wall, thus, greatly decreasing the likelihood of the appearance of strains resistance.

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

• Roscetto E, Contursi P, Vollaro A, Fusco S, Notomista E, Catania MR. Antifungal and anti-biofilm activity of the first cryptic antimicrobial peptide from an archaeal protein against Candida spp. clinical isolates. Sci Rep. 2018;8(1):17570

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.