DcP5 (cyclic and D-form of P5 peptide)

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

Batch to batch variation of the purity

DcP5 is a cyclic peptide derivative developed from the linear epitope peptide P5, which originates from the FGF2 sequence (LQLQAEER, amino acids 53-60). The cyclization is achieved by incorporating D-cysteine residues at both ends to form a disulfide bond, enhancing structural stability. DcP5 exhibits high binding affinity to fibroblast growth factor receptor 2 (FGFR2), with a dissociation constant (K_D) of 2.75 × 10^-9 M, competitively inhibiting FGFR2 activation by obstructing FGF2 interaction. Key residues Gln4 and Glu6 in the peptide are critical for FGFR2 binding, and their substitution abolishes this activity.

The cyclic structure of DcP5 confers improved in vivo stability and prolonged half-life compared to the linear P5 peptide. It effectively suppresses downstream signaling pathways, including phosphorylation of AKT and ERK1/2, leading to reduced cellular proliferation in FGFR2-expressing systems. This peptide demonstrates specific FGFR2-dependent activity and serves as a targeted inhibitor for studying FGFR2-related signaling mechanisms.

• Zhang Y, Ouyang M, Wang H, Zhang B, Guang W, Liu R, Li X, Shih TC, Li Z, Cao J, Meng Q, Su Z, Ye J, Liu F, Hong A, Chen X. A cyclic peptide retards the proliferation of DU145 prostate cancer cells in vitro and in vivo through inhibition of FGFR2. MedComm (2020). 2020 Dec 14;1(3):362-375. doi: 10.1002/mco2.48. PMID: 34766128; PMCID: PMC8491194.

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.