[A Paralytic shellfish poisoning GTX2,3 mimic peptide isolated from phage display: characterization and potential applications].

AIM

To screen peptide mimics of PSP (Paralytic shellfish poisoning) GTX2,3 from a random 12-mer phage display peptide library and to identify and characterize the specificity and accuracy of the peptide mimotope of GTX2,3.

METHODS

The monoclonal antibody against GTX2,3 (mAb E(9);F(10);) was used as a target to screen the 12-mer phage display peptide library and the specificity of phage clones were identified by sandwich ELISA and blocking assay. The peptide sequences of positive phage clones were determined and analyzed by DNA sequencing. The affinity and specificity of synthetic peptide were identified by a competitive ELISA.

RESULTS

The 20 clones were identified to be specific reactivity with the mAb E(9);F(10);. Amino acid sequence analysis revealed seven different types of mimotope sequence, most of which contained a common motif DXLXPP(X presents random acid amino), X was random amino acid. The Phage No.2(phage 2), the clone with mimotope sequence WPSLDXLXPPSY showed the strongest binding, and inhibited the reactivity of the mAb with GTX2,3. Another ELISA result showed that synthetic peptide-1 (SP-1) which contain mimotope amino acid sequence was able to inhibit the mAb- GTX2,3 interaction.

CONCLUSION

The mimotope peptide of GTX2,3 is obtained by using the phage display technology. The results also showed that SP-1 bind to mAb E(9);F(10); at the same site as GTX2,3.