Buforin I peptide

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

Batch to batch variation of the purity

Buforin I is a cationic antimicrobial peptide derived from histone proteins. It is a 39-amino acid peptide with a high proportion of basic residues, such as arginine and lysine, contributing to its strong positive charge. The peptide exhibits a broad spectrum of activity against various Gram-positive and Gram-negative bacteria and fungal strains. Structural analyses, including FTIR and modeling studies, indicate that Buforin I possesses an α-helical conformation, which is stabilized by the presence of a proline residue that introduces a hinge-like structure. This conformation is considered important for its functional interaction with microbial membranes.

Recombinant expression of Buforin I has been achieved in the periplasmic space of Escherichia coli using a pET-based system. The addition of a poly-histidine tag to the peptide's N-terminus facilitates purification via nickel affinity chromatography. Comparative studies between the native and His-tagged recombinant Buforin I reveal minimal differences in key physicochemical properties, including isoelectric point, net charge, and in silico stability parameters such as root mean square fluctuation (RMSF) and radius of gyration (Rg). The structural integrity and secondary α-helical conformation of the peptide are preserved following the His-tag fusion, as confirmed by spectroscopic methods.

• Roshanak, S., Yarabbi, H., Shahidi, F. et al. Effects of adding poly-histidine tag on stability, antimicrobial activity and safety of recombinant buforin I expressed in periplasmic space of Escherichia coli. Sci Rep 13, 5508 (2023). https://doi.org/10.1038/s41598-023-32782-3

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.