Three letter code
Peptide Purity (HPLC)
Infections caused by multidrug-resistant bacteria are a global emerging problem. New antibiotics that rely on innovative modes of action are urgently needed. Ranalexin is a potent antimicrobial peptide (AMP) produced in the skin of the American bullfrog Rana catesbeiana. Despite strong antimicrobial activity against Gram-positive bacteria, ranalexin shows disadvantages such as poor pharmacokinetics. To tackle these problems, a ranalexin derivative consisting exclusively of d-amino acids (named danalexin) was synthesized and compared to the original ranalexin for its antimicrobial potential and its biodistribution properties in a rat model. Danalexin showed improved biodistribution with an extended retention in the organisms ofWistar rats when compared to ranalexin. While ranalexin is rapidly cleared from the body, danalexin is retained primarily in the kidneys. Remarkably, both peptides showed strong antimicrobial activity against Gram-positive bacteria and Gram-negative bacteria of the genus Acinetobacter with minimum inhibitory concentrations (MICs) between 4 and 16 mg/L (1.9–7.6 M). Moreover, both peptides showed lower antimicrobial activities with MICs 32 mg/L (15.2 uM) against further Gram-negative bacteria. The preservation of antimicrobial activity proves that the configuration of the amino acids does not aect the anticipated mechanism of action, namely pore formation.
Ideally Ranalexin should be stored in a freezer at or below -9C. Ranalexin should be refrigerated after reconstitution. For more details, please refer to the manual:Handling and Storage of Synthetic Peptides
- Domhan C, Uhl P, Kleist C, et al. Replacement of l-Amino Acids by d-Amino Acids in the Antimicrobial Peptide Ranalexin and Its Consequences for Antimicrobial Activity and Biodistribution. Molecules. 2019;24(16)
About TFA salt
Trifluoroacetic acid (TFA) is a strong acid, which is commonly used to cleave synthesized peptides from solid-phase resins and is also used to improve HPLC performance in the peptide purification step. By default, custom peptides are delivered as lyophilized TFA salts, and can contain as much as 10-45% TFA.
TFA in custom peptides can cause inexplicable discrepancies in subsequent assay data. For instance, TFA in nM concentrations has been shown to interfere with cellular assays, inhibiting cellular proliferation in some instances, and increasing cell viability in others . It has also been found to be an unintended allosteric modulator of the glycine receptor, GlyR.
TFA Removal Service is recommended for:
- Peptides that will be used in cellular assays
- Peptides that will be used as APIs or in manufactured products
- For hydrophilic peptides containing numerous basic residues
- Analysed Sequence:H-FLGGLIKIVPAMICAVTKKC-OH
- Chemical Formula:C97H169N23O22S3
- Sequence length:20
- Extinction coefficient:0 M-1cm-1
- Mw average:2105.71
- Theoretical pI:9.8
- Data Source:Peptide Property Calculator
GRAVY = grand average of hydropathy
Red: Hydrophobic uncharged residues, like F I L M V W A and P
Blue: Basic residues, like R K H and N-terminal -NH2
Green: Acidic residues, like D E and C-terminal -COOH
Black: Polar uncharged residues, like G S T C N Q and Y
Related Products / Services
• Peptide Services: NovoPro's peptide synthesis services include standard chemical peptide synthesis, peptide modification, peptide libraries, and recombinant peptide expression.
• Standard Peptide Synthesis: NovoPro offers quality peptides at the most competitive prices in the industry, starting at $3.20 per amino acid. NovoPro provides PepBox – Automatic Quote Tool for online price calculation.
• Peptide Modifications: NovoPro offers a wide range of peptide modification services including isotope labeling (2H, 15N, and 13C), multiple disulfide bonds, multiple phosphorylations, KLH, BSA, ovalbumin, amidation, acetylation, biotin, FITC, etc.
Please note: All products are "FOR RESEARCH USE ONLY AND ARE NOT INTENDED FOR DIAGNOSTIC OR THERAPEUTIC USE"