BAR peptide

BAR peptide

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

Batch to batch variation of the purity

H-LEAAPKKVQDLLKKANITVKGAFQLFS-OH

H-Leu-Glu-Ala-Ala-Pro-Lys-Lys-Val-Gln-Asp-Leu-Leu-Lys-Lys-Ala-Asn-Ile-Thr-Val-Lys-Gly-Ala-Phe-Gln-Leu-Phe-Ser-OH

27

95.35%

C₁₃₇H₂₂₉N₃₅O₃₇

2958.48

Synthetic

Powder

BAR peptide is comprised of residues 1167 to 1193 of the SspB (Antigen I/II) protein sequence of S. gordonii (NH2-LEAAPKKVQDLLKKANITVKGAFQLFS-COOH). BAR peptide was developed that potently inhibits P. gingivalis/S. gordonii adherence in vitro and reduces P. gingivalis virulence in a mouse model of periodontitis. While efficacious, one of the challenges to free BAR administration is that it provides relatively transient inhibition of P. gingivalis in the oral cavity. Moreover, to treat established biofilms, relative to initial biofilm formation, higher concentrations of BAR are required.

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

• Daep, C. A., Novak, E. A., Lamont, R. J., and Demuth, D. R. (2011) Structural Dissection and in vivo Effectiveness of a Peptide Inhibitor of Porphyromonas gingivalis Adherence to Streptococcus gordonii. Infect. Immun. 79, 67-74.

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.