Circular dichroism and Fourier-transform infrared spectroscopies were used to compare the conformational mobility of 13-mer peptides covering the 317-329 region of the envelope protein hemagglutinin of human influenza A virus subtypes H1, H2 and H3 with that of their truncated deca- and nonapeptide analogs. These peptides were demonstrated to bind to the murine I-Ed major histocompatibility complex encoded class II and human HLA-B*2705 class I molecules. Despite the amino acid substitutions in the three 13-mer subtype sequences, no significant differences in the conformational properties could be shown. Deletion of the N-terminal three residues resulted in a shift to an increased α-helical conformer population in the 317-329 H1 peptide and the breakage of the 310 or weakly H-bonded (nascent) α-helix in the H2 and H3 peptides. The conformational change observed upon deletion did not influence the efficiency of I-Ed-peptide interaction, however, the C-terminal Arg had a beneficial effect both on MHC class II and class I binding without causing any remarkable change in solution conformation.
|Number of pages||9|
|Journal||Spectrochimica Acta - Part A: Molecular and Biomolecular Spectroscopy|
|Publication status||Published - Jan 2000|
ASJC Scopus subject areas
- Analytical Chemistry
- Atomic and Molecular Physics, and Optics