LfcinB6 peptide

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

Batch to batch variation of the purity

LfcinB6 (RRWQWR-NH2) is the antimicrobial core sequence of bovine lactoferricin (LfcinB), a 25-residue cationic antimicrobial peptide (AMP) derived from the N-terminal region of bovine lactoferrin. LfcinB6 represents the smallest motif of LfcinB that exhibits antimicrobial activity. It is a short, positively charged peptide that serves as a fundamental building block in the design of hybrid AMPs.

In a study, LfcinB6 was hybridized with KR-12-a4, a potent analog of the shortest antimicrobial sequence of human cathelicidin LL-37, to create a novel hybrid peptide designated Lf-KR. The two peptide segments were linked by a proline (Pro) hinge, which is known to provide cell selectivity by introducing a kink into the helical structure. The resulting Lf-KR hybrid peptide displayed broad-spectrum antimicrobial activities against a range of gram-positive and gram-negative bacteria, including antibiotic-resistant strains, and retained its antimicrobial activity in the presence of physiological salt concentrations. Mechanistic studies indicated that the enhanced antimicrobial activity of Lf-KR was due to increased permeabilization and depolarization of microbial membranes. Additionally, Lf-KR exhibited significant anti-biofilm activity, effectively disrupting preformed biofilms of multidrug-resistant Pseudomonas aeruginosa (MDRPA), as observed by confocal laser scanning microscopy.

• Richardson A, de Antueno R, Duncan R, Hoskin DW. Intracellular delivery of bovine lactoferricin's antimicrobial core (RRWQWR) kills T-leukemia cells. Biochem Biophys Res Commun. 2009 Oct 30;388(4):736-41. doi: 10.1016/j.bbrc.2009.08.083. Epub 2009 Aug 21. PMID: 19699713.
• Vega SC, Martínez DA, Chalá MDS, Vargas HA, Rosas JE. Design, Synthesis and Evaluation of Branched RRWQWR-Based Peptides as Antibacterial Agents Against Clinically Relevant Gram-Positive and Gram-Negative Pathogens. Front Microbiol. 2018 Mar 2;9:329. doi: 10.3389/fmicb.2018.00329. PMID: 29551999; PMCID: PMC5840262.
• Ajish C, Yang S, Kumar SD, Kim EY, Min HJ, Lee CW, Shin SH, Shin SY. A novel hybrid peptide composed of LfcinB6 and KR-12-a4 with enhanced antimicrobial, anti-inflammatory and anti-biofilm activities. Sci Rep. 2022 Mar 14;12(1):4365. doi: 10.1038/s41598-022-08247-4. PMID: 35288606; PMCID: PMC8921290.

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.