• Journal of Veterinary Science
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• v.22 no.4
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• pp.49.1-49.6
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• 2021

The S1 protein of the infectious bronchitis virus (IBV) is a major structural protein that induces the production of the virus-neutralization antibodies. The monoclonal antibody against the IBV M41 S1 protein was used as a target for biopanning. After three rounds of biopanning, randomly selected phages bound to the monoclonal antibody. Sequence analysis showed that the dominant sequence was SFYDFEMQGFFI. Indirect competitive enzyme-linked immunosorbent assay showed that SFYDFEMQGFFI is a mimotope of the S1 protein that was predicted by PepSurf. The mimotope may provide information for further structural and functional analyses of the S1 protein.

• Bulletin of the Korean Chemical Society
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• v.32 no.11
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• pp.4016-4020
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• 2011

A number of mimetic peptides of apolipoprotein A-I, a major component for high density lipoproteins (HDL), were screened from the phase-displayed random peptide library by utilizing monoclonal antibodies (A12). A mimetic peptide for A12 epitope against apolipoprotein A-I was selected as FVLVRDTFPSSVCCP(pA2) exhibiting 45% homology with Apo A-I in the BLAST search. Solution structure determination of this mimotope was made by using 2D-NMR data and NMR-based distance geometry (DG)/molecular dynamic calculations. The resulting DG structures had low penalty value of 0.4-0.6 ${\AA}^2$ and the total RMSD of 0.7-1.7 ${\AA}$. The mimotope pA2 exhibited a characteristic ${\beta}$-turn conformation from Val[2] to Phe[8] near Pro[9] residue.

• Bulletin of the Korean Chemical Society
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• v.32 no.9
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• pp.3425-3428
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• 2011

Apolipoprotein A-I (Apo A-I) is a major component for high density lipoproteins (HDL). A number of mimetic peptides of Apo A-I were screened from the phase-displayed random peptide library by utilizing monoclonal antibodies (A12). Mimetic peptide for A12 epitope against Apo A-I was selected as CPFARLPVEHHDVVGL (pA1). From the BLAST search, the mimetic peptide pA1 had 40% homology with Apo A-I. As a result of the structural determination of this mimotope using homo/hetero nuclear 2D-NMR techniques and NMR-based distance geometry (DG)/molecular dynamic (MD) computations, DG structure had low penalty value of 0.3-0.7 ${\AA}^2$ and the total RMSD was 0.6-1.6 ${\AA}$. The mimotope pA1 exhibited characteristic conformation including a ${\beta}$-turn from Pro[7] to His[11].

• IMMUNE NETWORK
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• v.1 no.1
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• pp.77-86
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• 2001

Background: Hepatitis C virus(HCV), a family of Flaviviridae, has a host cell-derived envelope containing a positive-stranded RNA genome, and has been known as the maj or etiological agent for chronic hepatitis, hepatic cirrhosis, and hepatocellular carcinoma. There remains a need to dissect a molecular mechanism of pathogenesis for the development of therapeutic and effective preventive measure for HCV. Identification of cellular receptor is of central importance not only to understand the viral pathogenesis, but also to exploit strategies for prevention of HCV. This study was aimed at identifying peptide mimotopes inhibiting the binding of E2 protein of HCV to MOLT-4 cell. Methods: In this study, phage peptide library displaying a random peptides consisting of 7 or 12 random peptides was employed in order to pan against E2 protein. Free HCV particles were separated from the immune complex forms by immunoprecipitation using anti-human IgG antibody, and used for HCV-capture ELISA. To identify the peptides inhibiting E2-binding to MOLT-4 cells, E2 protein was subj ect to bind to MOLT-4 cells under the competition with phage peptides. Results: Several phage peptides were selected for their specific binding to E2 protein, which showed the conserved sequence of SHFWRAP from 3 different peptide sequences. They were also able to recognize the HCV particles in the sera of HCV patients captured by monoclonal antibody against E2 protein. Two of them, showing peptide sequence of HLGPWMSHWFQR and WAPPLERSSLFY respectively, were revealed to inhibit the binding of E2 protein to MOLT-4 cell efficiently in dose dependent mode. However, few membrane-associated receptor candidates were seen using Fasta3 programe for homology search with these peptides. Conclusion: Phage peptides containing HLGPWMSHWFQR and WAPPLERSSLFY respectively, showed the inhibition of E2-binding to MOLT-4 cells. However, they did not reveal any homologues to cellular receptors from GenBank database. In further study, cellular receptor could be identified through the screening of cDNA library from MOLT-4 or hepatocytes using antibodies against these peptide mimotopes.

• Bulletin of the Korean Chemical Society
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• v.25 no.12
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• pp.1845-1849
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• 2004

Apolipoprotein B-100 (Apo-B100) is a major protein component for low density lipoproteins (LDL). A number of mimetic peptides of Apo-B100 were screened from the phase-displayed random peptide library by utilizing monoclonal antibody (B9). Mimetic peptide for B9 epitope against apo B-100 was CRNVPPIFNDVYWIAF (pB1). From the BLAST search, the mimetic peptide pB1 had 40% homology with apo B-100. As a result of the structural determination of this mimotope using homo/hetero nuclear 2D-NMR techniques and NMR-based distance geometry (DG)/molecular dynamic (MD) computations, DG structure had low penalty value of 0.3-0.6 ${\AA}^2$ and the total RMSD was 0.5-1.5 ${\AA}. Moreover, pB1 structure included a weak $3_{10}$-helix from $Ile^7$,/TEX> to $Trp^{13}$.

• BMB Reports
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• v.32 no.5
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• pp.461-467
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• 1999

Recombinant Mycobacterium smegmatis expressing ovalbumin was used to immunize C57BL/6(H-$2^b$) mice, and the humoral immunity against recombinant ovalbumin was analyzed. Antibodies were purified by denatured ovalbumin-conjugated affinity chromatography. The epitopes of the antibodies were screened with a random peptide library displayed on the tip of fUSE5 filamentous phage pIII minor coat proteins. Two peptides, IRLADR and SPGAEV, were selected predominantly by the recognition of purified antibodies using biopanning methods. The composition of the peptide sequence with the primary structure of OVA revealed that the peptide sequence analogizes to INEAGR, part of the $^{323}ISQAVHAAHAEINEAGR^{339}$ sequence previously reported as the antigenic determinant for murine Band also Th cell epitopes (I-$A^d$ binding). Also, the structures of these mimotopes obtained from restrained molecular dynamic computations resulted in the formation of a $\beta$-turn proven to be a secondary structure of the parent peptide within the ovalbumin molecule, enabling us to confirm the structural similarity. This study demonstrates that immunization with recombinant M. smegmatis can generate neutralizing antibodies identical with those induced by the administration of natural antigenic proteins and supports the potential use of mycobacteria as vaccine delivery vehicles.