| Autor: |
Cuniasse P; CEA, Département d'Ingénierie et d'Etudes des Protéines, Gif-sur-Yvette, France., Thomas A, Smith JC, Thanh HL, Léonetti M, Ménez A |
| Jazyk: |
angličtina |
| Zdroj: |
Biochemistry [Biochemistry] 1995 Oct 03; Vol. 34 (39), pp. 12782-9. |
| DOI: |
10.1021/bi00039a039 |
| Abstrakt: |
A synthetic octadecapeptide with the amino acid sequence of residues 23-40 of toxin alpha from Naja nigricollis, cyclized with a disulfide bridge between residues 23 and 40, induces antibodies that cross-react with toxin alpha. We report a structural analysis of this peptide in aqueous solution using NMR spectroscopy and molecular modeling. Structures compatible with the 151 obtained NMR distance restraints were generated using a random simulated annealing protocol followed by restrained high-temperature dynamics and energy minimization. The generated structures are compared with that of the corresponding sequence in the native toxin. The two stretches 23-28 and 37-40 adopt a canonical beta-strand structure in the toxin but are disordered in the peptide. The region 28-36 is ordered in both the peptide and the toxin. Residues 28-30 and 34-36 adopt beta-strand structures in the toxin but loop structures in the peptide. Residues 30-33 form a reverse turn in both the peptide and the toxin. Residues Val-27, Trp-28, Ile-35, and Ile-36 form a hydrophobic cluster. The similar, reverse-turn fold of residues 30-33 in the peptide and the toxin may be associated with the immunogenic cross-reactivity. |
| Databáze: |
MEDLINE |
| Externí odkaz: |
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