Enterocin X beta peptide

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

Batch to batch variation of the purity

Enterocin X is a novel two-peptide bacteriocin belonging to class IIb, produced by Enterococcus faecium KU-B5. It is composed of two complementary cationic peptides, Enterocin Xα (4,420.1 Da) and Enterocin Xβ (4,068.5 Da), which are 40 and 37 residues long, respectively. Both peptides contain GXXXG motifs associated with helix-helix interaction, and they exhibit synergistic antibacterial activity when combined, though the combined spectrum differs significantly from that of each individual peptide.

The structural genes enxA and enxB, encoding Enterocin Xα and Xβ, are organized in a single transcriptional unit, each encoding a prepeptide with a double-glycine-type leader sequence characteristic of class II bacteriocins. The genetic locus includes an upstream region with high sequence similarity to that of the enterocin B locus, suggesting potential shared transport mechanisms. Enterocin Xβ, along with Enterocin Xα, requires the complementary peptide for full antibacterial function, and their combined activity results in a bacteriocin entity with a distinct inhibitory profile against various bacterial indicators.

• Hu CB, Malaphan W, Zendo T, Nakayama J, Sonomoto K. Enterocin X, a novel two-peptide bacteriocin from Enterococcus faecium KU-B5, has an antibacterial spectrum entirely different from those of its component peptides. Appl Environ Microbiol. 2010 Jul;76(13):4542-5. doi: 10.1128/AEM.02264-09. Epub 2010 Apr 23. PMID: 20418437; PMCID: PMC2897431.

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.